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Archive 1 |
Summary section appears to have been vandalized. I see a Brave New World reference (2540s) and reference to the Lord of The Rings (Middle-Earth). - semi-anonymous 2009-10-20 18:34 —Preceding unsigned comment added by 198.185.66.249 ( talk)
The history section seems much too bulky to me. When this happens is it typical to break it off into its own separate article, or just pare it down? PitOfBabel 16:44, 31 July 2007 (UTC)
Overall I felt this article was not well organized, and I made changes to both shorten and clarify it.
I removed the "types of synthetic diamond" section and added a "properties of synthetic diamond" section instead. This isn't a perfect solution, as there are a couple of catch phrases in the old section that may need to be introduced again elsewhere. However, on the thole the "types" section merely listed what other sections already should have stated, and I don't think it was enlightening.
I also shortened the CVD diamond section and moved most of it to its own article. I'd actually like to do the same with HPHT if enough information can be added to warrant it.
The two important things that need to be done I haven't gotten to yet are to organize the applications section (group the applications under headings) and add more information about diamond gemstones and the confusion behind the word "synthetic". Let me know if you think this is heading in the right direction. PitOfBabel 17:42, 22 July 2007 (UTC)
Isn't any page about artificial diamonds incomplete without mentioning cubic zirconia's as diamond substitutes?
What about James Ballantyne (Hannay), I think (although it would require some verification) that he claimed to have produced very small synthetic diamonds in the 1880s by heating carbon under pressure in a kiln, a claim which was widely disputed at the time. However his 'diamonds' were sent to the british museum of natural history where upon rediscovery some years later they where found not only to be real diamonds, but also of a type consistent with synthetic construction.
The following sentence is contradictory:
"The yellow tint occurs when less than five out of each 100,000 carbon atoms in the diamond crystal lattice are replaced with nitrogen atoms. Technically it is a contaminant, but colored diamonds are more profitable because they can be made more quickly, cost less to manufacture, and are very popular".
The part that says "Technically it is a contaminant, but [...]" implies that there is too much contaminant. Which is wrong ! Because the synthetic process naturally leads to these low levels of contaminant (nitrogen atoms).
Or maybe the error is that "[...] when less than five out of [...]" should be replaced by "[...] when more than five out of [...]". In this case the sentence would be perfectly logical. -- R. Duxx
Another statement is contradictory:
"[it] uses the low-pressure technique of chemical vapor deposition (CVD) to produce [diamonds]. The diamond produced is a single crystal, as opposed to the polycrystalline patchworks formerly produced by CVD."
So basically it says "it uses CVD to produce diamonds which are not like the ones produced by CVD". What a pity, after having read this article about diamonds, I am now even more confused...
Can anyone explain why "Synthetic diamonds retain ultraviolet light just as well as any type of light while natural diamonds usually retain light outside the visible spectrum poorly"? If LP CVD produces chemically & physically correct diamonds, why should they exhibit different spectral properties? Frankie 04:13, 1 January 2006 (UTC)
(A process) developed by Gemesis, makes diamonds that may contain impurities in about 100 hours, by mimicing the natural process.
Statements where reasonable people may disagree
A minor nit, but its HPHT rather than HTHP when used as an acronym in the industry.
Also, Gemesis did not develop HPHT, they refined the reproduceability of the process using the smaller BARS system. The russians (at Novosibirsk) invented the washing machine size BARS press, which Gemesis imported and refined. -- CarbonElemental 06:57, 23 December 2005 (UTC)
CVD, chemical vapor deposition, builds diamonds by precipitation from carbon plasma and builds up at half a millimeter a day, and has a theoretical limit of several inches.
Statements where reasonable people may disagree
~ender 2004-09-04 MST 19:22
One has to be careful with the price statement because it is not really clear what industrial CVD diamond really is. If it is a polycrystalline material, then indeed it can be rather cheap because it grows on various substrates (Si, glass, etc.) and the growth parameters are not really that demanding. On the contrary, the monocrystalline material is grown only on diamond (usually Ib HPHT) and Ir substrates and is very slow, as was pointed out, what makes the price rather high. Colour of the final layer depends on the process, now it is possible to grow layers which are rather pure and suitable for electronic application. If someone is interested I would advice to have a look at Elsevier's journal "Diamond and related materials". ~And 2005-10-5
There is an apparent contradiction between the claim that CVD single crystal diamonds cannot be grown to more than a few millimeters in radius and the claim that the Carnegie Institute's process can be extended to grow a 300 carrot stone. Logicnazi 07:54, 12 February 2007 (UTC)
I'm somehow skeptical that only two minor companies should be listed as making synthetic industrial diamonds. I was under the impression that the technique existed quite before these companies (not for making diamonds suitables for jewelry, but for making diamonds for industrial uses, i.e. tools). David.Monniaux 05:02, 11 May 2005 (UTC)
I was under the impression that nickel is used as a catalyst/solvent in the production of industrial diamonds. If someone can find a source for this, it should really be in the article.-- Joel 8 July 2005 01:51 (UTC)
The information posted below by “samboy” on 26 September 2005 is false and misleading. No where on the our website does Diamond Nexus Labs, Inc. “admit they are selling CZ”. To our knowledge “samboy” has not done any scientific analysis of the chemical composition and physical properties of our gemstones. The Diamond Nexus gemstone is a complex polycrystalline substance, and detailed information on our gemstone science is available on our site. Deeper information, including the complete chemical rubric for the stone is available by contacting customerservice@diamondnexuslabs.com.
Wikipedia has been notified that “samboys” posting is erroneous, oversimplified and uses trademarked information without our permission.
There are a number of places out there that sell Cubic zirconia marketed as a "synthetic diamond". These are not diamonds; the gems in question are not made out of compressed Carbon. Diamond Nexus labs admits they're selling CZ here (ZrO2 is the chemical formula for Cubic zirconia); Russian Stone Company admits it here: "If a natural diamond jeweler uses a natural diamond tester on a synthetic Russian stone, they will most likely, in error, state that our product is a standard cubic zirconia. This is not true, our synthetic Russian Stones will not change color or clarity and are so durable that it will scratch glass.". On This page it states "Russian Diamonds: Including Russian Brilliants, Russian Stars and others, they are in fact nothing but high quality cubic zirconias. This is not mentioned prominently on their web sites and they will only cop to it when pressed, but that is the fact." (Of course, the same is true for the "Diamonds" that Diamond Nexus Labs sells). Samboy 09:56, 26 September 2005 (UTC)
An anonymous poster removed the section on CVD diamond problems, writing: "removing the "problems." CVD research has largely been exhausted. Other methods do not depend on surface area, so problem 2 is meaningless. And CVD is no longer slow."
Working in the field I can state emphatically that CVD research is hardly exhausted; on the contrary, it is experiencing a revival across the world. While research funding has shown boom-bust cycles in the US, other parts of the world have been making steady progress, especially Asia. There are many areas that have not been adequately researched, such as the most effective method of diamond n-type doping, the most acceptable method of radiation detection, methods of depositing uniform diamond, doped uniformly over large substrate areas, etc.
Surface area is a very serious issue for CVD diamond growth. What the anon revisionist means by "other methods do not depend on surface area" would be interesting to find out. There are some recent breakthroughs in microwave plasma CVD that have improved sufrace area, but the uniformity is questionable and reproducibility low. I think Fraunhoffer has made progress in that area, but they haven't had much of an impact on the market. I am certain there is no US company producing large diamond wafers in any significant quantity; otherwise the navy wouldn't be beating down doors looking for a supplier for radar windows. As for non-microwave based plasmas, arcjet still only coats small areas. Only hot filament shows much promise for area, but this comes at a high cost; the chemistry at tungsten filaments is even more complex (in undesirable ways) than in other plasma systems. I know of companies that coat larger areas with hot filament reactors, but their growth rates are incredibly low.
Saying CVD is no longer slow suggests a lack of understanding about how diverse the area is. There have recently been some really incredible growth rates demonstrated at a few universities, but these are the exception rather than the rule. They operate in very specific parameters (very high pressure/power) that cannot be used in other circumstances. Deposition rates such as these cannot be done on most substrates (such as silicon) for many reasons, especially thermal stability of the substrate and adhesion. So it is true that some CVD isn't slow, but is absolutely not true that CVD isn't slow.
The anon person did make a great point though by adding another problem to the list; economics is a very serious issue for CVD diamond. However, note that this is primarily because of the problems they erased. Methane, hydrogen and electricity are cheap. The problem preventing economic success in most areas is quality of the diamond, surface area coated and rate of coating.
Comments welcome.
PitOfBabel 21:35, 15 December 2005 (UTC)
It seems that many are using the term CVD synonymously with polycrystalline. I haven't found homoepitaxi mentioned anywhere. See also the Marchywka Effect links, lots of good citations. I guess with nanotubes and actual deployment by Euroepans of a VUV detector, as well as supconductivity, adding to buckeyballs soot and pencils, there is a lot to cover. Not sure how best to organize it but no where on wiki did I see homoepi...
Nerdseeksblonde ( talk) 13:02, 26 June 2009 (UTC)
The Chemical vapor deposition, CVD section mentions sp3 bonded carbon, I could find no information anywhere on wikipedia about an sp3 bond, only an sp2 bond. What is an sp3 bond and should an article be created for it? -- Atlanta800 21:56, 15 February 2006 (UTC)
Someone added the following to the page: "White diamonds, however, are still lacking in clarity, and at projected costs, do not offer any greater value for the price ( http://diamondcuttersintl.com/diamond_education/articles/reference/apollo.html), ( http://www.gia.edu/newsroom/issue/2798/1842/insider_newsletter_details.cfm#3)"
Both of those articles are several years old, neither makes any real argument about the price, and the "lacking in clarity" business is a poor assertion not validated by either article. There is no doubt Apollo is having issues; they were supposed to be selling gems back in 2004, and still don't have any significant number on the shelves. I would be interesting hearing real reasons why this could be, but neither of those articles really gives answers. Removing until someone provides better evidence for these opinionated assertions.
PitOfBabel 14:12, 14 March 2006 (UTC)
From the GIA article: "Clarity was equivalent to VS1 to SI2; some small and irregularly shaped gray-black inclusions were observed in some samples, due to deposition of diamond-like carbon or graphite (as suggested by Raman spectroscopy)." Compared to other synthetic gem diamonds (Gemesis), the maximum clarity (VS1) is significantly lacking by comparison to "internally flawless" ( http://www.gemesis.com/specs_3.htm). Also note that the only white diamond produced by Apollo that I could find reference to on the web (see GIA article) is tiny at 14 points. By all accounts, Apollo diamonds tend to be brown (not white). Perhaps I should have noted the color issue to start. Yes, both of these articles are several years old, but they are the most recent, and the GIA article is one of, if not the only, technical description of Apollo diamonds. Some parts of this section read like a press release from the marketing department. I suggest other references to the price of Apollo diamonds (even relative statements like "cheaper than natural") be removed, since no evidence is cited to support those claims.
Damian: Apollo Jewelry was "coming soon" back in November of 2003. If it's alright, let's just say their gemstones are not available, and we'll update when they actually are. PitOfBabel 16:16, 11 April 2006 (UTC)
I am considering creating a new article for CVD diamond growth and leaving a short introduction here. I've been busy, but I suspect I will take care of this in June.
Any comments, or objections? PitOfBabel 13:50, 27 May 2006 (UTC)
This just got moved from the category Diamond to the category Synthetic Diamond. This doesn't make sense to me. It seems to me that this should still be left in the category Diamond as well. Making the change; if you disagree post here please.
I don't know if this is true, but I heard, unrelaibly, that some funeral homes are taking the carbon of dead people and turning it to diamond for their famillies...sort of a fancy advance on the urn of ashes...
What is the cost per stone of making synthetic gem-quality diamonds by these various processes? -- Beland 16:54, 20 December 2006 (UTC)
The consumable materials involved in HPHT are highly refined and purified in order to achieve gem-quality results, and are not inexpensive. The growth units and the labor costs of the scientists are the largest costs involved. Each machine runs for one full cycle lasting many days to weeks, though many times the diamond may have stopped growing part way through, or became so heavily included, the usable gem-quality is minimal. The failure rate is still high which causes the overall costs to go up. Once a rough is available, the costs are very similar to the mined diamond industry. Cutting a rough diamond is usually a few hundred dollars per carat of rough. It is not uncommon to have 50% or more loss of material from rough to polished. Though the costs are not revealed by the manufacturers, the retail prices are readily available from the gem-quality manufacturers websites ( example). In general for a one carat, an orange yellow is around $2,500, a yellow is around $4,000, a blue is around $10,000 and a colorless is around $6,000. EEFranklin ( talk) 21:32, 4 March 2009 (UTC)
In the "Synthetic Gems" section, the article states that "Colored diamonds are more profitable because they can be made more quickly, cost less to manufacture, and are very popular." My understanding is that colored diamonds are substantially less valuable on the market than clear diamonds. Clear diamond is 100 times more expensive than black diamond, and it is also substantially more valuable than the yellow diamond that is often found in mines. Gemologists often discuss the clarity of diamonds, as this is a deteriming factor in their value. Thus if synthetic diamonds are colored, and not clear, then they are LESS profitable compared to clear ones (not MORE profitable). It is also stated that "...greater measure of control allows Apollo Diamond to produce diamonds of various colors, from pink to black." I think that the assertion about colored diamonds being more profitable is an error and should be corrected. Colored diamonds are less valuable than clear ones and black diamond is worthless for gems (black diamond is used only for industrial purposes). I also think that there should be some mention of whether or not there currently exists a known process for the synthesis of CLEAR diamonds. --Anonymous 11:36, 24 December 2006 (UTC)
(UTC)
Someone requested a citation for the following - "As such, it shares the same material properties and is potentially of an even higher quality than its natural counterpart." The problem isn't that this needs a citation so much as it is possibly subjective. Obviously natural diamond has impurities due to the conditions it is created in. There is no argument that CVD diamond growth can produce diamond with far fewer impurities. That might be worth citing, except that the level of impurities is not necessarily a key indicator of quality. That's the whole point of doping - you can sometimes get better results with specific amounts of key "impurities".
I'll think about how it might be rewritten. In the meantime though it doesn't need citations so much as it needs clarification.
An example of where synthetic diamond is superior to natural diamond is in hardness. Consider Rev. Sci. Instrum. 76, 026112 (2005), Super-hard diamond indenter prepared from high-purity synthetic diamond crystal. Also consider this link: http://www.carnegieinstitution.org/raining_gems.html. That was a simple google search because I knew what to look for, I haven't tried Elsevier yet.
Maybe instead of "higher quality than" we could have "superior in some aspects to". Sounds poorly worded, but might lead to a fair solution. PitOfBabel 21:25, 26 February 2007 (UTC)
Someone has misunderstood the title and has began describing how properties of diamonds are observed. Instead, the section should list and detail the properties of a synthetic diamond. Can someone please remove and add information regarding the properties of a synthetic diamond, and possibly comparisons to a ground diamond. -- 78.86.117.164 23:58, 6 October 2007 (UTC)
The comment(s) below were originally left at Talk:Synthetic diamond/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
A peer review for this article would be beneficial. It may be GA, and could advance to FA with some additional work. Inline citations appear at a cursory glance to be partly in place. SauliH 06:50, 5 February 2007 (UTC) |
Last edited at 06:52, 5 February 2007 (UTC). Substituted at 15:54, 1 May 2016 (UTC)
The term synthetic diamond implies that it is somehow artificial and not the same as natural diamond (which is a neutral term). Isn't Man-made a better term, the synthetic diamond page could just link there. — Preceding unsigned comment added by 195.184.122.26 ( talk • contribs) 14:11, 21 April 2007 (UTC)
So I am not so sure it's a recent campaign by the natural diamond companies (i.e. de Beers). it is pretty clear that in scientific circles, "synthetic" means from synthesized material and that is exactly what this type of diamond is. Obviously 90 % or more of the synthetic diamonds are used in industry. I am pretty neutral about it, "lab-created" or "artifical" diamond would be a pretty proper name as well. I am curious as to what you mean with the public impression of "synthetic diamonds" that is not true...
Gem-fanat 22:21, 12 July 2007 (UTC)
Gem-fanat 15:57, 13 July 2007 (UTC)
DONE !!! Gem-fanat 16:01, 13 July 2007 (UTC)
Moved from article:
As the previous posters have pointed out, the term "synthetic diamond" predates any of the terms such as "cultured" or "lab-grown" which are used by the people who market synthetic diamonds, and it is therefore not part of a De Beers conspiracy. As has also been discussed, the fact that something is "synthetic" doesn't make it worse, as opposed to "artificial diamonds" which are not diamonds at all, and could more correctly be termed ersatz diamonds or diamond substitutes. It is true that in the gem trade, "diamonds are all about emotion". As larger quantities of synthetic diamond become available, people will increasingly be faced with the decision of whether to buy a smaller mined diamond or a larger synthetic diamond, and this will moderate the emotion involved. To make my allegiances clear: I work for a health food and supplement company, and am not in any way funded by De Beers. My wife and I are not emotional about diamonds and precious metals, and we both wear stainless steel wedding bands. -- Slashme ( talk) 10:52, 7 December 2007 (UTC)
Thanks for responding so quickly. I hope you are alerted to messages here. I think your conclusion that the term synthetic is neutral is mistaken. I will assume that you are correct that "synthetic" predates "lab-grown," but the fact that DeBeer's did not pioneer the term does not preclude their marketing teams from trying to brand these gems as "synthetic." Furthermore, your use of the word conspiracy leads me to believe that you might not understand why I find the term lacking neutrality. Of coarse if there was a secret conspiracy to use the word, it would be biased, but that is not what I am contending. I am simply pointing out what is undisputed -- marketing teams are trying to equate these gems with the word "synthetic." Branding like this is very common and falls quite short of any conspiracy theory, but still makes it a non-neutral term. Words and their connotations are extremely influential. That is precisely why the makers of diamonds want them to be called "cultured." Because this article chooses "synthetic" for its title, it declares one camp the winner.
I agree that there are persuasive arguments for identifying them as synthetic, but what I found shocking about this purportedly neutral piece is that it did not even mention this debate. What reason is there for not including a one-line disclosure.
My bias is obvious: I think synthetic is misleading, and I also think that the word carries a negative connotation in the eyes of ordinary consumers. That said, I would never contend an article would be comprehensive if it did not at least mention the merits for using the word synthetic. —Preceding unsigned comment added by 146.145.190.179 ( talk) 00:24, 8 December 2007 (UTC)
--
My name's Justin Richards. I'm a journalist who has researched lab-created diamonds. The problem with synthetic is that it describes the combination, or synthesis, of two different elements. That is the definition given by Merriam Webster. Diamond formation, on the other hand, involves pure Carbon only. —Preceding unsigned comment added by 71.16.142.42 ( talk) 19:06, 28 March 2008 (UTC)
I agree Synthetic diamond is a loaded term. I would suggest anthropologic diamond or geologic diamond if we need to differentiate whether they are formed as a result of human action or geologic action. After all, you might build a factory (as opposed to a lab) to make diamonds which are every bit as practically useful as geological diamonds to mount on a metal band on a finger.
The usefulness of a diamond on a band is as a result of the ideas it is imbued with, which has been achieved through clever marketing paid for through prices achieved as a result of scarcity. Forgetting the ideas diamond is imbued with, cubic zirconia is just as functional as a gem stone as diamond. We need to remember that diamonds formed through geologic processes have a range of properties in terms of contaminants. Those contaminants appear to be the method to distinguish anthropologic vs geological. It appears the quality and contaminant components of anthropologic diamonds can be very closely controlled using CVD. It is therefore not reasonable to assume that geologic vs anthropologic diamonds can be reliably distinguished today. As mentioned above, it will be increasingly difficult to continue the illusion of scarcity as manufacturing techniques improve. Techniques will likely continue to improve as there are many industrial uses for crystalline carbon. As scarcity falls, and marketing margins fall, we may need to find some other scarce material to imbue the ideas formerly associated with Diamond. DeBeers - You will have to find something other than Diamond! Nick Hill ( talk) 15:27, 2 July 2013 (UTC)
3000 degrees Celsius is NOT 5432K. To convert from Celsius to Kelvin you add 273. Now I don't want to make the edit because I don't know which value is correct but this is a glaring error. 124.185.183.122 22:31, 6 September 2007 (UTC)
Since the diamond structure is cubic, with space group Fd3m (see for example the "Manual of Mineralogy" 21st edition by Klein and Hurlbut"), I changed "tetragonal carbon allotrope" to "cubic carbon allotrope". Wikimedes 07:17, 2 December 2007 (UTC)
I found and analyzed the original paper JACS 126 (2004) 3191 but saw no proof of diamond synthesis and therefore deleted the "Preceramic polymer" section. Even if the JACS authors were correct in producing diamond, the result is very poorly described and should be
1) Confirmed by other authors. I should note an inconsistency in that JACS paper. The only evidence of diamond is the Raman spectrum, but it is way too sharp for such a synthesis, and the 1320 peak suddenly shifts to 1276 cm-1 upon changing the laser wavelength, which is much too suspicious.
2) Properly described. This Wikipedia article picked up the creams of that paper (easy low-temperature synthesis) whereas the actual growth took 121 hr at 1120 C in Ar flow + 24 hr at 1300 C in air and had very low "diamond" yield. Anybody who tried knows how difficult it is to convert carbon into diamond :-) NIMSoffice ( talk) 00:46, 16 December 2008 (UTC)
To NIMSoffice and Materialscientist:
First, we provided bona-fide references - three of them - to back up the poly(hydridocarbyne) entry in Lonsdaleite. Neither one of you have provided a *single* contrary reference to backup your subjective comments.
Second, the JACS 126 (2004) 3191 paper we referenced was peer-revived in one of the most prestigious journals in America - a very high standard for accuracy indeed.
Third, if either of you had bothered to read the other two references we provided you would have found the corroborating X-ray evidence from other authors (Toppare et al):
page 361, section 3.2, Characterization of Diamond, para 2: "The X-ray powder pattern of the ~mixture shows it to consist of Lonsdaleite" from: Toppare L et al. (May 2008). "Facile Synthesis of Poly(hydridocarbyne): A Precursor to Diamond and Diamond-like Ceramics". Journal of Macromolecular Science, Part A 45 (5): 358–363. doi:10.1080/10601320801946108.
page 2776, para 2: "The data represents Lonsdaleite, a hexagonal form of diamond the fit is even better than the one in aprevious work": Toppare L et al. (June 2009). "Electrochemical polymerizatıon of hexachloroethane to form poly(hydridocarbyne): a pre-ceramic polymer for diamond production". Journal of Materials Science 44 (11): 2774-2779. doi:10.1007/s10853-009-3364-4. —Preceding unsigned comment added by SixFingeredMan ( talk • contribs) 23:48, 5 August 2009 (UTC)
"The mined diamond industry is evaluating marketing and distribution countermeasures to these less expensive alternatives." need quotation to verify
"The three largest distributors have made public statements about selling their diamonds with full disclosure and have implemented measures to laser-inscribe serial numbers on their gemstones." - The external reference only mentions one company stating their intent to laser inscribe. Should this be rephrased? Furthermore, Gemesis only sells rough diamonds so they cannot laser inscribe the polished diamonds. EEFranklin ( talk) 22:04, 4 March 2009 (UTC)
After a quick scan I've found some MOS issues, listed below. I have not given the article a full review yet, and will wait until the major MOS issues are resolved before doing so.
The intro is still too small. --
ErgoSum88 (
talk)
17:24, 5 May 2009 (UTC)
On second thought, the lead image and images of detailed diagrams may be sized larger to allow better viewing, but normally no larger than 300px, so I changed some of them around so it would look better. -- ErgoSum88 ( talk) 17:24, 5 May 2009 (UTC)
I fixed some. Note that journal citations do not need access date and publisher. Regarding {{ cite journal}}, I prefer using much shorter style, which is much easier to type and read in plain text (cf. the codes of this [1] and this [2] references; note that most GAs have ~50 of them and that {{ cite journal}} is very sensitive; e.g., Title instead of title will be ignored), but I shall change it to {{ cite journal}} if required? This is a non-issue. NIMSoffice ( talk) 00:26, 5 May 2009 (UTC)
{{
cite journal}}
: |last=
has generic name (
help)
I think I have covered everything, and I haven't even given the article my "thorough" review yet. On second thought, this probably would have qualified as a quickfail, as it might take longer than seven days to fix all the issues. But the seven day limit is mostly a suggestion and as long as I receive a reply within seven days I am willing to overlook the time limit. If an editor has not expressed an interest in addressing these issues within seven days, that is usually when I fail the article. So... good luck! -- ErgoSum88 ( talk) 15:25, 3 May 2009 (UTC)
Reading the article, I have come across some issues, listed below.
I have also made numerous minor edits to the article to improve readability and understanding. Although I have taken care not to change anything I didn't understand, please check to be sure I haven't changed anything I shouldn't have. -- ErgoSum88 ( talk) 19:38, 5 May 2009 (UTC)
Very well done. And thanks for adding the proper cite templates, it looks much better now. Good job, article passed, and here is your green circle! -- ErgoSum88 ( talk) 00:53, 7 May 2009 (UTC)
I believe 1882-1922 is 40 years, not 30... though I cannot find the correct information to clarify it. Syhon ( talk) 13:17, 20 October 2009 (UTC)
After the first unsuccessful FA nomination, the Enlgish style of the article was brushed up as reflected here. Materialscientist ( talk) 23:15, 3 June 2009 (UTC)
The article is good on the technology side but not on the socioeconomics.
The article only indirectly indicates why anyone would bother to make synthetic diamond rather than using natural diamond. I would have assumed it was purely because of price; the #Economics section on this Talk page has a bit of information, but the article itself does not. Having read the article, it seems that another advantage of synthesis is that you can fine-tune the properties of the resulting diamond to be atypical or unknown among natural diamonds; this is implicit in the Properties section but never actually stated. I presume this tuning will also affect the price.
Also, the article is very circumspect about the use of synthetics in jewellery/gemstones. It seems POV to focus on the opposition of the natural-diamond companies. What about their competitors? How widespread are they? How much cheaper? How do consumers value "naturalness" against price? (The #Synthetic diamond is a loaded term section above is relevant for this.) Given that diamonds are conspicuous consumption, is price-based competition even feasible? Are there cases of fraud, passing synthetics off as natural? Are firms making efforts to fool the DiamondView and/or make nature-identical synthetics? jnestorius( talk) 09:51, 20 October 2009 (UTC)
The ashes from a cremation are sometimes used to make a diamond to be used as a gemstone for sentimental reasons. Should there be a section on this? —Preceding unsigned comment added by 62.12.14.27 ( talk) 09:59, 20 October 2009 (UTC)
The article refers to one potential use of synthetic diamond being "high-power switches at power stations". Being an electrical transmission engineer, I expect what this means to say is "high-voltage switchgear on transmission systems", but I would need to read the full paper to be sure. It's referenced to: J. Isberg, M. Gabrysch, A. Tajani, and D.J. Twitchen (2006). " High-field Electrical Transport in Single Crystal CVD Diamond Diodes", Advances in Science and Technology 48:73, but that link leads only to the abstract and first paragraph. Does anyone have access to the full paper they could share with me? Thanks, — BillC talk 17:20, 20 October 2009 (UTC)
This phrase is a little preposterous "Numerous claims of diamond synthesis were documented between 1879 and 1928; each of those attempts were carefully analyzed and none were confirmed." Every claim was carefully examine? I am sure there were a number of claims that were just brushed off. Which is fine as science is not required to carefully examine and refute every bogus claim. But saying all were examined without references is a little far fetched. Doc James ( talk · contribs · email) 19:31, 20 October 2009 (UTC)
Is there a reason this sentence is in the middle of a history section? Did it occur at some auspicious time? Could a knowledgeable editor relocate this statement or else give it the needed context? Comet Tuttle ( talk) 22:54, 20 October 2009 (UTC)
I noticed the discussion above, which talks about the article name, and whether it should be called "synthetic" or "cultured". It seems to me that the term "cultured diamonds" exists in the industry as being different from squishing a bunch of carbon together, but instead refers to "growing" from a seed.
So, if synthetic covers all non-natural diamonds, and "cultured" diamonds describes a process and a product that is a subset of synthetic, then shouldn't we have a section (namely the Synthetic diamond#Later developments section), named "cultured diamonds" or "culturing diamonds"? Am I a making any sense? What do you think? Anna Frodesiak ( talk) 13:49, 6 February 2011 (UTC)
(By the way, I did notice Chemical vapor deposition of diamond. But that just confused me.) Anna Frodesiak ( talk) 13:51, 6 February 2011 (UTC)
It would be interesting to have a graph of the price of diamonds (of a certain size or quality or whatever) produced by different technologies over time. In particular, I'm wondering what the impact of synthetic diamonds on the natural diamond market is. -- Beland ( talk) 01:18, 3 June 2012 (UTC)
The section on hardness lacked any mention of polycrystalline diamond, or PCD (which is synthetic Carbonado), so I added it with links to other articles at Wikipedia which support this. However, it needs direct citation from scientific sources (I don't know but that this article, http://en.wikipedia.org/wiki/Material_properties_of_diamond#cite_note-11 cited in the article Material properties of diamond, may illuminate that. I have run across information on the hardness of all known forms of diamond in GPa, but don't recall where now--and I think it would be useful to compare the different forms of diamond listed in this section, in those terms (GPa). Also, it may be worth noting that several times, Tracy Hall accidentally synthesized ballast (opaque white PCD, which accomplishment was announced in this paper, I believe -- http://www.sciencemag.org/content/169/3948/868.abstract -- and reproduced here also http://www.htracyhall.org/papers/19700427.pdf -- and there seems to be no mention of ballast diamond anywhere on Wikipedia), and that this has not yet been reproduced, and that no one has yet synthesized Lonsdaleite (which is about five times harder than monocrystal diamond) either. Both of these, with theoretical GPa, could be added somewhere here--perhaps under a section entitled "Forms of Diamond Which Have Not Been Synthesized" -- perhaps that could be a sub-section of "Hardness". -- RichardAlexanderHall ( talk) 16:28, 16 December 2012 (UTC)
Under the section "Impurities and inclusions", it says "Every diamond contains atoms other than carbon in concentrations detectable by analytical techniques." However, under the section "Thermal conductivity", it talks about " isotopically pure diamond" that is " Single crystals of synthetic diamond enriched in 12C (99.9%)" according to this article, but "100% 12C or 100% 13C" according to the isotopically pure diamond article. It is my understanding that these diamonds do not have "atoms other than carbon" and invalidates the "Every diamond" statement. Alancnet ( talk) 05:09, 18 August 2014 (UTC)
This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 |
Summary section appears to have been vandalized. I see a Brave New World reference (2540s) and reference to the Lord of The Rings (Middle-Earth). - semi-anonymous 2009-10-20 18:34 —Preceding unsigned comment added by 198.185.66.249 ( talk)
The history section seems much too bulky to me. When this happens is it typical to break it off into its own separate article, or just pare it down? PitOfBabel 16:44, 31 July 2007 (UTC)
Overall I felt this article was not well organized, and I made changes to both shorten and clarify it.
I removed the "types of synthetic diamond" section and added a "properties of synthetic diamond" section instead. This isn't a perfect solution, as there are a couple of catch phrases in the old section that may need to be introduced again elsewhere. However, on the thole the "types" section merely listed what other sections already should have stated, and I don't think it was enlightening.
I also shortened the CVD diamond section and moved most of it to its own article. I'd actually like to do the same with HPHT if enough information can be added to warrant it.
The two important things that need to be done I haven't gotten to yet are to organize the applications section (group the applications under headings) and add more information about diamond gemstones and the confusion behind the word "synthetic". Let me know if you think this is heading in the right direction. PitOfBabel 17:42, 22 July 2007 (UTC)
Isn't any page about artificial diamonds incomplete without mentioning cubic zirconia's as diamond substitutes?
What about James Ballantyne (Hannay), I think (although it would require some verification) that he claimed to have produced very small synthetic diamonds in the 1880s by heating carbon under pressure in a kiln, a claim which was widely disputed at the time. However his 'diamonds' were sent to the british museum of natural history where upon rediscovery some years later they where found not only to be real diamonds, but also of a type consistent with synthetic construction.
The following sentence is contradictory:
"The yellow tint occurs when less than five out of each 100,000 carbon atoms in the diamond crystal lattice are replaced with nitrogen atoms. Technically it is a contaminant, but colored diamonds are more profitable because they can be made more quickly, cost less to manufacture, and are very popular".
The part that says "Technically it is a contaminant, but [...]" implies that there is too much contaminant. Which is wrong ! Because the synthetic process naturally leads to these low levels of contaminant (nitrogen atoms).
Or maybe the error is that "[...] when less than five out of [...]" should be replaced by "[...] when more than five out of [...]". In this case the sentence would be perfectly logical. -- R. Duxx
Another statement is contradictory:
"[it] uses the low-pressure technique of chemical vapor deposition (CVD) to produce [diamonds]. The diamond produced is a single crystal, as opposed to the polycrystalline patchworks formerly produced by CVD."
So basically it says "it uses CVD to produce diamonds which are not like the ones produced by CVD". What a pity, after having read this article about diamonds, I am now even more confused...
Can anyone explain why "Synthetic diamonds retain ultraviolet light just as well as any type of light while natural diamonds usually retain light outside the visible spectrum poorly"? If LP CVD produces chemically & physically correct diamonds, why should they exhibit different spectral properties? Frankie 04:13, 1 January 2006 (UTC)
(A process) developed by Gemesis, makes diamonds that may contain impurities in about 100 hours, by mimicing the natural process.
Statements where reasonable people may disagree
A minor nit, but its HPHT rather than HTHP when used as an acronym in the industry.
Also, Gemesis did not develop HPHT, they refined the reproduceability of the process using the smaller BARS system. The russians (at Novosibirsk) invented the washing machine size BARS press, which Gemesis imported and refined. -- CarbonElemental 06:57, 23 December 2005 (UTC)
CVD, chemical vapor deposition, builds diamonds by precipitation from carbon plasma and builds up at half a millimeter a day, and has a theoretical limit of several inches.
Statements where reasonable people may disagree
~ender 2004-09-04 MST 19:22
One has to be careful with the price statement because it is not really clear what industrial CVD diamond really is. If it is a polycrystalline material, then indeed it can be rather cheap because it grows on various substrates (Si, glass, etc.) and the growth parameters are not really that demanding. On the contrary, the monocrystalline material is grown only on diamond (usually Ib HPHT) and Ir substrates and is very slow, as was pointed out, what makes the price rather high. Colour of the final layer depends on the process, now it is possible to grow layers which are rather pure and suitable for electronic application. If someone is interested I would advice to have a look at Elsevier's journal "Diamond and related materials". ~And 2005-10-5
There is an apparent contradiction between the claim that CVD single crystal diamonds cannot be grown to more than a few millimeters in radius and the claim that the Carnegie Institute's process can be extended to grow a 300 carrot stone. Logicnazi 07:54, 12 February 2007 (UTC)
I'm somehow skeptical that only two minor companies should be listed as making synthetic industrial diamonds. I was under the impression that the technique existed quite before these companies (not for making diamonds suitables for jewelry, but for making diamonds for industrial uses, i.e. tools). David.Monniaux 05:02, 11 May 2005 (UTC)
I was under the impression that nickel is used as a catalyst/solvent in the production of industrial diamonds. If someone can find a source for this, it should really be in the article.-- Joel 8 July 2005 01:51 (UTC)
The information posted below by “samboy” on 26 September 2005 is false and misleading. No where on the our website does Diamond Nexus Labs, Inc. “admit they are selling CZ”. To our knowledge “samboy” has not done any scientific analysis of the chemical composition and physical properties of our gemstones. The Diamond Nexus gemstone is a complex polycrystalline substance, and detailed information on our gemstone science is available on our site. Deeper information, including the complete chemical rubric for the stone is available by contacting customerservice@diamondnexuslabs.com.
Wikipedia has been notified that “samboys” posting is erroneous, oversimplified and uses trademarked information without our permission.
There are a number of places out there that sell Cubic zirconia marketed as a "synthetic diamond". These are not diamonds; the gems in question are not made out of compressed Carbon. Diamond Nexus labs admits they're selling CZ here (ZrO2 is the chemical formula for Cubic zirconia); Russian Stone Company admits it here: "If a natural diamond jeweler uses a natural diamond tester on a synthetic Russian stone, they will most likely, in error, state that our product is a standard cubic zirconia. This is not true, our synthetic Russian Stones will not change color or clarity and are so durable that it will scratch glass.". On This page it states "Russian Diamonds: Including Russian Brilliants, Russian Stars and others, they are in fact nothing but high quality cubic zirconias. This is not mentioned prominently on their web sites and they will only cop to it when pressed, but that is the fact." (Of course, the same is true for the "Diamonds" that Diamond Nexus Labs sells). Samboy 09:56, 26 September 2005 (UTC)
An anonymous poster removed the section on CVD diamond problems, writing: "removing the "problems." CVD research has largely been exhausted. Other methods do not depend on surface area, so problem 2 is meaningless. And CVD is no longer slow."
Working in the field I can state emphatically that CVD research is hardly exhausted; on the contrary, it is experiencing a revival across the world. While research funding has shown boom-bust cycles in the US, other parts of the world have been making steady progress, especially Asia. There are many areas that have not been adequately researched, such as the most effective method of diamond n-type doping, the most acceptable method of radiation detection, methods of depositing uniform diamond, doped uniformly over large substrate areas, etc.
Surface area is a very serious issue for CVD diamond growth. What the anon revisionist means by "other methods do not depend on surface area" would be interesting to find out. There are some recent breakthroughs in microwave plasma CVD that have improved sufrace area, but the uniformity is questionable and reproducibility low. I think Fraunhoffer has made progress in that area, but they haven't had much of an impact on the market. I am certain there is no US company producing large diamond wafers in any significant quantity; otherwise the navy wouldn't be beating down doors looking for a supplier for radar windows. As for non-microwave based plasmas, arcjet still only coats small areas. Only hot filament shows much promise for area, but this comes at a high cost; the chemistry at tungsten filaments is even more complex (in undesirable ways) than in other plasma systems. I know of companies that coat larger areas with hot filament reactors, but their growth rates are incredibly low.
Saying CVD is no longer slow suggests a lack of understanding about how diverse the area is. There have recently been some really incredible growth rates demonstrated at a few universities, but these are the exception rather than the rule. They operate in very specific parameters (very high pressure/power) that cannot be used in other circumstances. Deposition rates such as these cannot be done on most substrates (such as silicon) for many reasons, especially thermal stability of the substrate and adhesion. So it is true that some CVD isn't slow, but is absolutely not true that CVD isn't slow.
The anon person did make a great point though by adding another problem to the list; economics is a very serious issue for CVD diamond. However, note that this is primarily because of the problems they erased. Methane, hydrogen and electricity are cheap. The problem preventing economic success in most areas is quality of the diamond, surface area coated and rate of coating.
Comments welcome.
PitOfBabel 21:35, 15 December 2005 (UTC)
It seems that many are using the term CVD synonymously with polycrystalline. I haven't found homoepitaxi mentioned anywhere. See also the Marchywka Effect links, lots of good citations. I guess with nanotubes and actual deployment by Euroepans of a VUV detector, as well as supconductivity, adding to buckeyballs soot and pencils, there is a lot to cover. Not sure how best to organize it but no where on wiki did I see homoepi...
Nerdseeksblonde ( talk) 13:02, 26 June 2009 (UTC)
The Chemical vapor deposition, CVD section mentions sp3 bonded carbon, I could find no information anywhere on wikipedia about an sp3 bond, only an sp2 bond. What is an sp3 bond and should an article be created for it? -- Atlanta800 21:56, 15 February 2006 (UTC)
Someone added the following to the page: "White diamonds, however, are still lacking in clarity, and at projected costs, do not offer any greater value for the price ( http://diamondcuttersintl.com/diamond_education/articles/reference/apollo.html), ( http://www.gia.edu/newsroom/issue/2798/1842/insider_newsletter_details.cfm#3)"
Both of those articles are several years old, neither makes any real argument about the price, and the "lacking in clarity" business is a poor assertion not validated by either article. There is no doubt Apollo is having issues; they were supposed to be selling gems back in 2004, and still don't have any significant number on the shelves. I would be interesting hearing real reasons why this could be, but neither of those articles really gives answers. Removing until someone provides better evidence for these opinionated assertions.
PitOfBabel 14:12, 14 March 2006 (UTC)
From the GIA article: "Clarity was equivalent to VS1 to SI2; some small and irregularly shaped gray-black inclusions were observed in some samples, due to deposition of diamond-like carbon or graphite (as suggested by Raman spectroscopy)." Compared to other synthetic gem diamonds (Gemesis), the maximum clarity (VS1) is significantly lacking by comparison to "internally flawless" ( http://www.gemesis.com/specs_3.htm). Also note that the only white diamond produced by Apollo that I could find reference to on the web (see GIA article) is tiny at 14 points. By all accounts, Apollo diamonds tend to be brown (not white). Perhaps I should have noted the color issue to start. Yes, both of these articles are several years old, but they are the most recent, and the GIA article is one of, if not the only, technical description of Apollo diamonds. Some parts of this section read like a press release from the marketing department. I suggest other references to the price of Apollo diamonds (even relative statements like "cheaper than natural") be removed, since no evidence is cited to support those claims.
Damian: Apollo Jewelry was "coming soon" back in November of 2003. If it's alright, let's just say their gemstones are not available, and we'll update when they actually are. PitOfBabel 16:16, 11 April 2006 (UTC)
I am considering creating a new article for CVD diamond growth and leaving a short introduction here. I've been busy, but I suspect I will take care of this in June.
Any comments, or objections? PitOfBabel 13:50, 27 May 2006 (UTC)
This just got moved from the category Diamond to the category Synthetic Diamond. This doesn't make sense to me. It seems to me that this should still be left in the category Diamond as well. Making the change; if you disagree post here please.
I don't know if this is true, but I heard, unrelaibly, that some funeral homes are taking the carbon of dead people and turning it to diamond for their famillies...sort of a fancy advance on the urn of ashes...
What is the cost per stone of making synthetic gem-quality diamonds by these various processes? -- Beland 16:54, 20 December 2006 (UTC)
The consumable materials involved in HPHT are highly refined and purified in order to achieve gem-quality results, and are not inexpensive. The growth units and the labor costs of the scientists are the largest costs involved. Each machine runs for one full cycle lasting many days to weeks, though many times the diamond may have stopped growing part way through, or became so heavily included, the usable gem-quality is minimal. The failure rate is still high which causes the overall costs to go up. Once a rough is available, the costs are very similar to the mined diamond industry. Cutting a rough diamond is usually a few hundred dollars per carat of rough. It is not uncommon to have 50% or more loss of material from rough to polished. Though the costs are not revealed by the manufacturers, the retail prices are readily available from the gem-quality manufacturers websites ( example). In general for a one carat, an orange yellow is around $2,500, a yellow is around $4,000, a blue is around $10,000 and a colorless is around $6,000. EEFranklin ( talk) 21:32, 4 March 2009 (UTC)
In the "Synthetic Gems" section, the article states that "Colored diamonds are more profitable because they can be made more quickly, cost less to manufacture, and are very popular." My understanding is that colored diamonds are substantially less valuable on the market than clear diamonds. Clear diamond is 100 times more expensive than black diamond, and it is also substantially more valuable than the yellow diamond that is often found in mines. Gemologists often discuss the clarity of diamonds, as this is a deteriming factor in their value. Thus if synthetic diamonds are colored, and not clear, then they are LESS profitable compared to clear ones (not MORE profitable). It is also stated that "...greater measure of control allows Apollo Diamond to produce diamonds of various colors, from pink to black." I think that the assertion about colored diamonds being more profitable is an error and should be corrected. Colored diamonds are less valuable than clear ones and black diamond is worthless for gems (black diamond is used only for industrial purposes). I also think that there should be some mention of whether or not there currently exists a known process for the synthesis of CLEAR diamonds. --Anonymous 11:36, 24 December 2006 (UTC)
(UTC)
Someone requested a citation for the following - "As such, it shares the same material properties and is potentially of an even higher quality than its natural counterpart." The problem isn't that this needs a citation so much as it is possibly subjective. Obviously natural diamond has impurities due to the conditions it is created in. There is no argument that CVD diamond growth can produce diamond with far fewer impurities. That might be worth citing, except that the level of impurities is not necessarily a key indicator of quality. That's the whole point of doping - you can sometimes get better results with specific amounts of key "impurities".
I'll think about how it might be rewritten. In the meantime though it doesn't need citations so much as it needs clarification.
An example of where synthetic diamond is superior to natural diamond is in hardness. Consider Rev. Sci. Instrum. 76, 026112 (2005), Super-hard diamond indenter prepared from high-purity synthetic diamond crystal. Also consider this link: http://www.carnegieinstitution.org/raining_gems.html. That was a simple google search because I knew what to look for, I haven't tried Elsevier yet.
Maybe instead of "higher quality than" we could have "superior in some aspects to". Sounds poorly worded, but might lead to a fair solution. PitOfBabel 21:25, 26 February 2007 (UTC)
Someone has misunderstood the title and has began describing how properties of diamonds are observed. Instead, the section should list and detail the properties of a synthetic diamond. Can someone please remove and add information regarding the properties of a synthetic diamond, and possibly comparisons to a ground diamond. -- 78.86.117.164 23:58, 6 October 2007 (UTC)
The comment(s) below were originally left at Talk:Synthetic diamond/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.
A peer review for this article would be beneficial. It may be GA, and could advance to FA with some additional work. Inline citations appear at a cursory glance to be partly in place. SauliH 06:50, 5 February 2007 (UTC) |
Last edited at 06:52, 5 February 2007 (UTC). Substituted at 15:54, 1 May 2016 (UTC)
The term synthetic diamond implies that it is somehow artificial and not the same as natural diamond (which is a neutral term). Isn't Man-made a better term, the synthetic diamond page could just link there. — Preceding unsigned comment added by 195.184.122.26 ( talk • contribs) 14:11, 21 April 2007 (UTC)
So I am not so sure it's a recent campaign by the natural diamond companies (i.e. de Beers). it is pretty clear that in scientific circles, "synthetic" means from synthesized material and that is exactly what this type of diamond is. Obviously 90 % or more of the synthetic diamonds are used in industry. I am pretty neutral about it, "lab-created" or "artifical" diamond would be a pretty proper name as well. I am curious as to what you mean with the public impression of "synthetic diamonds" that is not true...
Gem-fanat 22:21, 12 July 2007 (UTC)
Gem-fanat 15:57, 13 July 2007 (UTC)
DONE !!! Gem-fanat 16:01, 13 July 2007 (UTC)
Moved from article:
As the previous posters have pointed out, the term "synthetic diamond" predates any of the terms such as "cultured" or "lab-grown" which are used by the people who market synthetic diamonds, and it is therefore not part of a De Beers conspiracy. As has also been discussed, the fact that something is "synthetic" doesn't make it worse, as opposed to "artificial diamonds" which are not diamonds at all, and could more correctly be termed ersatz diamonds or diamond substitutes. It is true that in the gem trade, "diamonds are all about emotion". As larger quantities of synthetic diamond become available, people will increasingly be faced with the decision of whether to buy a smaller mined diamond or a larger synthetic diamond, and this will moderate the emotion involved. To make my allegiances clear: I work for a health food and supplement company, and am not in any way funded by De Beers. My wife and I are not emotional about diamonds and precious metals, and we both wear stainless steel wedding bands. -- Slashme ( talk) 10:52, 7 December 2007 (UTC)
Thanks for responding so quickly. I hope you are alerted to messages here. I think your conclusion that the term synthetic is neutral is mistaken. I will assume that you are correct that "synthetic" predates "lab-grown," but the fact that DeBeer's did not pioneer the term does not preclude their marketing teams from trying to brand these gems as "synthetic." Furthermore, your use of the word conspiracy leads me to believe that you might not understand why I find the term lacking neutrality. Of coarse if there was a secret conspiracy to use the word, it would be biased, but that is not what I am contending. I am simply pointing out what is undisputed -- marketing teams are trying to equate these gems with the word "synthetic." Branding like this is very common and falls quite short of any conspiracy theory, but still makes it a non-neutral term. Words and their connotations are extremely influential. That is precisely why the makers of diamonds want them to be called "cultured." Because this article chooses "synthetic" for its title, it declares one camp the winner.
I agree that there are persuasive arguments for identifying them as synthetic, but what I found shocking about this purportedly neutral piece is that it did not even mention this debate. What reason is there for not including a one-line disclosure.
My bias is obvious: I think synthetic is misleading, and I also think that the word carries a negative connotation in the eyes of ordinary consumers. That said, I would never contend an article would be comprehensive if it did not at least mention the merits for using the word synthetic. —Preceding unsigned comment added by 146.145.190.179 ( talk) 00:24, 8 December 2007 (UTC)
--
My name's Justin Richards. I'm a journalist who has researched lab-created diamonds. The problem with synthetic is that it describes the combination, or synthesis, of two different elements. That is the definition given by Merriam Webster. Diamond formation, on the other hand, involves pure Carbon only. —Preceding unsigned comment added by 71.16.142.42 ( talk) 19:06, 28 March 2008 (UTC)
I agree Synthetic diamond is a loaded term. I would suggest anthropologic diamond or geologic diamond if we need to differentiate whether they are formed as a result of human action or geologic action. After all, you might build a factory (as opposed to a lab) to make diamonds which are every bit as practically useful as geological diamonds to mount on a metal band on a finger.
The usefulness of a diamond on a band is as a result of the ideas it is imbued with, which has been achieved through clever marketing paid for through prices achieved as a result of scarcity. Forgetting the ideas diamond is imbued with, cubic zirconia is just as functional as a gem stone as diamond. We need to remember that diamonds formed through geologic processes have a range of properties in terms of contaminants. Those contaminants appear to be the method to distinguish anthropologic vs geological. It appears the quality and contaminant components of anthropologic diamonds can be very closely controlled using CVD. It is therefore not reasonable to assume that geologic vs anthropologic diamonds can be reliably distinguished today. As mentioned above, it will be increasingly difficult to continue the illusion of scarcity as manufacturing techniques improve. Techniques will likely continue to improve as there are many industrial uses for crystalline carbon. As scarcity falls, and marketing margins fall, we may need to find some other scarce material to imbue the ideas formerly associated with Diamond. DeBeers - You will have to find something other than Diamond! Nick Hill ( talk) 15:27, 2 July 2013 (UTC)
3000 degrees Celsius is NOT 5432K. To convert from Celsius to Kelvin you add 273. Now I don't want to make the edit because I don't know which value is correct but this is a glaring error. 124.185.183.122 22:31, 6 September 2007 (UTC)
Since the diamond structure is cubic, with space group Fd3m (see for example the "Manual of Mineralogy" 21st edition by Klein and Hurlbut"), I changed "tetragonal carbon allotrope" to "cubic carbon allotrope". Wikimedes 07:17, 2 December 2007 (UTC)
I found and analyzed the original paper JACS 126 (2004) 3191 but saw no proof of diamond synthesis and therefore deleted the "Preceramic polymer" section. Even if the JACS authors were correct in producing diamond, the result is very poorly described and should be
1) Confirmed by other authors. I should note an inconsistency in that JACS paper. The only evidence of diamond is the Raman spectrum, but it is way too sharp for such a synthesis, and the 1320 peak suddenly shifts to 1276 cm-1 upon changing the laser wavelength, which is much too suspicious.
2) Properly described. This Wikipedia article picked up the creams of that paper (easy low-temperature synthesis) whereas the actual growth took 121 hr at 1120 C in Ar flow + 24 hr at 1300 C in air and had very low "diamond" yield. Anybody who tried knows how difficult it is to convert carbon into diamond :-) NIMSoffice ( talk) 00:46, 16 December 2008 (UTC)
To NIMSoffice and Materialscientist:
First, we provided bona-fide references - three of them - to back up the poly(hydridocarbyne) entry in Lonsdaleite. Neither one of you have provided a *single* contrary reference to backup your subjective comments.
Second, the JACS 126 (2004) 3191 paper we referenced was peer-revived in one of the most prestigious journals in America - a very high standard for accuracy indeed.
Third, if either of you had bothered to read the other two references we provided you would have found the corroborating X-ray evidence from other authors (Toppare et al):
page 361, section 3.2, Characterization of Diamond, para 2: "The X-ray powder pattern of the ~mixture shows it to consist of Lonsdaleite" from: Toppare L et al. (May 2008). "Facile Synthesis of Poly(hydridocarbyne): A Precursor to Diamond and Diamond-like Ceramics". Journal of Macromolecular Science, Part A 45 (5): 358–363. doi:10.1080/10601320801946108.
page 2776, para 2: "The data represents Lonsdaleite, a hexagonal form of diamond the fit is even better than the one in aprevious work": Toppare L et al. (June 2009). "Electrochemical polymerizatıon of hexachloroethane to form poly(hydridocarbyne): a pre-ceramic polymer for diamond production". Journal of Materials Science 44 (11): 2774-2779. doi:10.1007/s10853-009-3364-4. —Preceding unsigned comment added by SixFingeredMan ( talk • contribs) 23:48, 5 August 2009 (UTC)
"The mined diamond industry is evaluating marketing and distribution countermeasures to these less expensive alternatives." need quotation to verify
"The three largest distributors have made public statements about selling their diamonds with full disclosure and have implemented measures to laser-inscribe serial numbers on their gemstones." - The external reference only mentions one company stating their intent to laser inscribe. Should this be rephrased? Furthermore, Gemesis only sells rough diamonds so they cannot laser inscribe the polished diamonds. EEFranklin ( talk) 22:04, 4 March 2009 (UTC)
After a quick scan I've found some MOS issues, listed below. I have not given the article a full review yet, and will wait until the major MOS issues are resolved before doing so.
The intro is still too small. --
ErgoSum88 (
talk)
17:24, 5 May 2009 (UTC)
On second thought, the lead image and images of detailed diagrams may be sized larger to allow better viewing, but normally no larger than 300px, so I changed some of them around so it would look better. -- ErgoSum88 ( talk) 17:24, 5 May 2009 (UTC)
I fixed some. Note that journal citations do not need access date and publisher. Regarding {{ cite journal}}, I prefer using much shorter style, which is much easier to type and read in plain text (cf. the codes of this [1] and this [2] references; note that most GAs have ~50 of them and that {{ cite journal}} is very sensitive; e.g., Title instead of title will be ignored), but I shall change it to {{ cite journal}} if required? This is a non-issue. NIMSoffice ( talk) 00:26, 5 May 2009 (UTC)
{{
cite journal}}
: |last=
has generic name (
help)
I think I have covered everything, and I haven't even given the article my "thorough" review yet. On second thought, this probably would have qualified as a quickfail, as it might take longer than seven days to fix all the issues. But the seven day limit is mostly a suggestion and as long as I receive a reply within seven days I am willing to overlook the time limit. If an editor has not expressed an interest in addressing these issues within seven days, that is usually when I fail the article. So... good luck! -- ErgoSum88 ( talk) 15:25, 3 May 2009 (UTC)
Reading the article, I have come across some issues, listed below.
I have also made numerous minor edits to the article to improve readability and understanding. Although I have taken care not to change anything I didn't understand, please check to be sure I haven't changed anything I shouldn't have. -- ErgoSum88 ( talk) 19:38, 5 May 2009 (UTC)
Very well done. And thanks for adding the proper cite templates, it looks much better now. Good job, article passed, and here is your green circle! -- ErgoSum88 ( talk) 00:53, 7 May 2009 (UTC)
I believe 1882-1922 is 40 years, not 30... though I cannot find the correct information to clarify it. Syhon ( talk) 13:17, 20 October 2009 (UTC)
After the first unsuccessful FA nomination, the Enlgish style of the article was brushed up as reflected here. Materialscientist ( talk) 23:15, 3 June 2009 (UTC)
The article is good on the technology side but not on the socioeconomics.
The article only indirectly indicates why anyone would bother to make synthetic diamond rather than using natural diamond. I would have assumed it was purely because of price; the #Economics section on this Talk page has a bit of information, but the article itself does not. Having read the article, it seems that another advantage of synthesis is that you can fine-tune the properties of the resulting diamond to be atypical or unknown among natural diamonds; this is implicit in the Properties section but never actually stated. I presume this tuning will also affect the price.
Also, the article is very circumspect about the use of synthetics in jewellery/gemstones. It seems POV to focus on the opposition of the natural-diamond companies. What about their competitors? How widespread are they? How much cheaper? How do consumers value "naturalness" against price? (The #Synthetic diamond is a loaded term section above is relevant for this.) Given that diamonds are conspicuous consumption, is price-based competition even feasible? Are there cases of fraud, passing synthetics off as natural? Are firms making efforts to fool the DiamondView and/or make nature-identical synthetics? jnestorius( talk) 09:51, 20 October 2009 (UTC)
The ashes from a cremation are sometimes used to make a diamond to be used as a gemstone for sentimental reasons. Should there be a section on this? —Preceding unsigned comment added by 62.12.14.27 ( talk) 09:59, 20 October 2009 (UTC)
The article refers to one potential use of synthetic diamond being "high-power switches at power stations". Being an electrical transmission engineer, I expect what this means to say is "high-voltage switchgear on transmission systems", but I would need to read the full paper to be sure. It's referenced to: J. Isberg, M. Gabrysch, A. Tajani, and D.J. Twitchen (2006). " High-field Electrical Transport in Single Crystal CVD Diamond Diodes", Advances in Science and Technology 48:73, but that link leads only to the abstract and first paragraph. Does anyone have access to the full paper they could share with me? Thanks, — BillC talk 17:20, 20 October 2009 (UTC)
This phrase is a little preposterous "Numerous claims of diamond synthesis were documented between 1879 and 1928; each of those attempts were carefully analyzed and none were confirmed." Every claim was carefully examine? I am sure there were a number of claims that were just brushed off. Which is fine as science is not required to carefully examine and refute every bogus claim. But saying all were examined without references is a little far fetched. Doc James ( talk · contribs · email) 19:31, 20 October 2009 (UTC)
Is there a reason this sentence is in the middle of a history section? Did it occur at some auspicious time? Could a knowledgeable editor relocate this statement or else give it the needed context? Comet Tuttle ( talk) 22:54, 20 October 2009 (UTC)
I noticed the discussion above, which talks about the article name, and whether it should be called "synthetic" or "cultured". It seems to me that the term "cultured diamonds" exists in the industry as being different from squishing a bunch of carbon together, but instead refers to "growing" from a seed.
So, if synthetic covers all non-natural diamonds, and "cultured" diamonds describes a process and a product that is a subset of synthetic, then shouldn't we have a section (namely the Synthetic diamond#Later developments section), named "cultured diamonds" or "culturing diamonds"? Am I a making any sense? What do you think? Anna Frodesiak ( talk) 13:49, 6 February 2011 (UTC)
(By the way, I did notice Chemical vapor deposition of diamond. But that just confused me.) Anna Frodesiak ( talk) 13:51, 6 February 2011 (UTC)
It would be interesting to have a graph of the price of diamonds (of a certain size or quality or whatever) produced by different technologies over time. In particular, I'm wondering what the impact of synthetic diamonds on the natural diamond market is. -- Beland ( talk) 01:18, 3 June 2012 (UTC)
The section on hardness lacked any mention of polycrystalline diamond, or PCD (which is synthetic Carbonado), so I added it with links to other articles at Wikipedia which support this. However, it needs direct citation from scientific sources (I don't know but that this article, http://en.wikipedia.org/wiki/Material_properties_of_diamond#cite_note-11 cited in the article Material properties of diamond, may illuminate that. I have run across information on the hardness of all known forms of diamond in GPa, but don't recall where now--and I think it would be useful to compare the different forms of diamond listed in this section, in those terms (GPa). Also, it may be worth noting that several times, Tracy Hall accidentally synthesized ballast (opaque white PCD, which accomplishment was announced in this paper, I believe -- http://www.sciencemag.org/content/169/3948/868.abstract -- and reproduced here also http://www.htracyhall.org/papers/19700427.pdf -- and there seems to be no mention of ballast diamond anywhere on Wikipedia), and that this has not yet been reproduced, and that no one has yet synthesized Lonsdaleite (which is about five times harder than monocrystal diamond) either. Both of these, with theoretical GPa, could be added somewhere here--perhaps under a section entitled "Forms of Diamond Which Have Not Been Synthesized" -- perhaps that could be a sub-section of "Hardness". -- RichardAlexanderHall ( talk) 16:28, 16 December 2012 (UTC)
Under the section "Impurities and inclusions", it says "Every diamond contains atoms other than carbon in concentrations detectable by analytical techniques." However, under the section "Thermal conductivity", it talks about " isotopically pure diamond" that is " Single crystals of synthetic diamond enriched in 12C (99.9%)" according to this article, but "100% 12C or 100% 13C" according to the isotopically pure diamond article. It is my understanding that these diamonds do not have "atoms other than carbon" and invalidates the "Every diamond" statement. Alancnet ( talk) 05:09, 18 August 2014 (UTC)