| Revision as of 03:39, 13 February 2005 editJasper (talk | contribs)Extended confirmed users1,162 editsm →Is clarity grading done using a standard distance from eye-to-stone?: Updated link -- source moved.← Previous edit |
Latest revision as of 01:41, 17 December 2024 edit undoAntiDionysius (talk | contribs)Extended confirmed users, Pending changes reviewers, Rollbackers39,318 editsm Reverted edits by 2600:1700:14BE:E00:50ED:D441:7C50:A161 (talk) to last version by TollensTag: Rollback |
| Line 1: |
Line 1: |
|
{{source}} |
|
{{Talk header}} |
|
|
{{American English}} |
|
|
{{Article history |
|
|
|action1=FAC |
|
|
|action1date=22:06, 10 Mar 2005 |
|
|
|action1link=Misplaced Pages:Featured article candidates/Diamond/archive1 |
|
|
|action1result=fail |
|
|
|action1oldid=11005667 |
|
|
|
|
|
|
|action2=FAC |
|
== Folklore == |
|
|
|
|action2date=00:11, 16 Apr 2005 |
|
|
|
|
|
|
|action2link=Misplaced Pages:Featured article candidates/Diamond |
|
If the folklore section is not corroborated by some kind of reference I or someone else can check, I'm removing it in a few days. I am not an expert at the occult, but I do know a bit, and it doesn't jive with this stuff. It may be the belief of some group somewhere, but it's not general occultist belief, so it needs context or I'm erasing it. --] |
|
|
|
|action2result=promoted |
|
|
|action2oldid=12371192 |
|
|
|
|
|
|
|action3=FTC |
|
It was written by ]. When asked, he said it came from notes he's collected over the years. He appears to come from a tradition of ]. See his home page at http://members.tripod.com/Corvus13/ — maybe that will give some insight into his POV. ''<>< ]'' |
|
|
|
|action3date=23 January 2007 |
|
|
|action3link=Misplaced Pages:Featured topic candidates/Diamond/archive1 |
|
|
|action3result=fail |
|
|
|action3oldid=102714557 |
|
|
|
|
|
|
|action4=FAR |
|
|
|action4date=00:45, 25 August 2009 |
|
|
|action4link=Misplaced Pages:Featured article review/Diamond/archive1 |
|
|
|action4result=kept |
|
|
|action4oldid=309682489 |
|
|
|
|
|
|
|maindate=May 11, 2005 |
|
== thanks for the help!!!! == |
|
|
|
|currentstatus=FA |
|
I logged onto this site to search Diamond realated industries in & around South India, I must say that I had a very good SouthIndian tour. Very informative as to the culture,music,regions etc. Well, I was totally lost in going through the very minute detail. Can somebody help me in providing the details of the Diamond related industries/research institutes. |
|
|
|
|itndate=17 January 2010 |
|
|
}} |
|
|
{{WikiProject banner shell|class=FA|collapsed=yes|vital=yes|1= |
|
|
{{WikiProject Gemology and Jewelry|gemstones=yes|importance=top}} |
|
|
{{WikiProject Africa|importance=mid|South Africa=yes|Angola=yes|Botswana=yes|Botswana-importance=High|Sierra Leone=yes|Sierra Leone-importance=High}} |
|
|
{{WikiProject Russia|importance=low}} |
|
|
{{WikiProject Canada|importance=low}} |
|
|
{{WikiProject Metalworking|importance=Low}} |
|
|
{{WikiProject Rocks and minerals|importance=Mid}} |
|
|
{{WikiProject Spoken Misplaced Pages}} |
|
|
{{WikiProject Geology|importance=Mid}} |
|
|
}} |
|
|
{{Press|org=]|articlename=David Williamson's column|url=http://icwales.icnetwork.co.uk/0100news/0600uk/tm_objectid=14291990&method=full&siteid=50082&headline=-name_page.html|June 2004|wikilink=] |
|
|
|year2=2004|section2=June 2004 (17 articles) |
|
|
|title2=Untitled David Williamson column. |
|
|
|org2=The Western Mail |
|
|
|date2=June 1, 2004 |
|
|
|url2=http://icwales.icnetwork.co.uk/0100news/0600uk/tm_objectid=14291990&method=full&siteid=50082&headline=-name_page.html}} |
|
|
{{Connected contributor (paid)|User1=RockMagnetist (DCO visiting scholar)|U1-employer=Deep Carbon Observatory|U1-client= Deep Carbon Observatory|U1-otherlinks=}} |
|
|
{{section size}} |
|
|
{{Spoken Misplaced Pages request|Catfurball|Important}} |
|
|
<!--- Auto archiving configured by ] ---> |
|
|
{{User:MiszaBot/config |
|
|
|algo = old(180d) |
|
|
|archive = Talk:Diamond/Archive %(counter)d |
|
|
|counter = 8 |
|
|
|maxarchivesize = 150K |
|
|
|archiveheader = {{tan}} |
|
|
|minthreadstoarchive = 1 |
|
|
|minthreadsleft = 4 |
|
|
}} |
|
|
|
|
|
|
== Move discussion in progress == |
|
Thanks & Regards |
|
|
|
|
|
|
|
There is a move discussion in progress on ] which affects this page. Please participate on that page and not in this talk page section. Thank you. <!-- Talk:Diamond the Body#Requested move 29 July 2023 crosspost --> —] 10:17, 29 July 2023 (UTC) |
|
Keshava |
|
|
|
|
|
|
|
== Chemistry == |
|
|
|
|
|
|
Wow, is this a bad article. The lead states:"Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen)." This is absolute rubbish. It isn't its "rigidity" that gives bulk diamond its impermeability (if that's what is meant by contamination). It is easy to "contaminate" a diamond CVD film with you name it. How big is the difference between contaminating a 1 inch cube (say) of pure iron vs. pure diamond? Not much. Ion implantation into (the near surface of) a diamond is also trivial. If the editors meant that NATURAL diamonds (on Earth) are typically quite pure, then SAY THAT! I suspect, but just an ignorant suspicion, that diamond must transition between impure high-carbon 'stuff' to the pure allotrope. I expect that at some point there's LOTS of contaminants in the nascent diamond. Aren't most natural diamonds black? What's that?? (the preceding is a digression, I'm ignorant on their natural occurrence.) There are so many FALSE statements in this article that it needs a total rewrite. There are many other bloopers but I don't have the patience to list them all. (For instance, did you know that hydrogen will leave an ash when burnt? No? Well, just read this article. When a diamond burns (in O2), any contaminants are left as ash. Ridiculous. (as is the assumption of complete combustion of the carbon) Another false claim is that diamond contains the most atoms per unit volume. (aside: at first, I thought the editor meant per unit cell volume!, not sure why s/he used the word "unit" since it doesn't add clarity (but it is not wrong)). Estimates of hydrogen density in the sun's core is ~10,000 kg/m^3, and without qualifying pressure and temperature the claim is likely false. I could go on...)] (]) 20:59, 20 August 2023 (UTC) |
|
hi im ashley a 15 year old freshman high school. i had to pick an meneral for a science project and i chose diamonds. ure site was very imformative. thanks for ure help!!!!! i got almost everything i needed for my 3 page report! |
|
|
|
:Don't forget that vinyl will wear down a diamond!! ] (]) <!--Template:Undated--><small class="autosigned">— Preceding ] comment added 21:17, 13 September 2023 (UTC)</small> <!--Autosigned by SineBot--> |
|
thanks again! |
|
|
|
== Featured picture scheduled for POTD == |
|
~oooohhhhhhbaby@aol.com |
|
|
---- |
|
|
Mostly minor corrections, additions and copyediting. |
|
|
|
|
|
|
|
Hello! This is to let editors know that ], a ] used in this article, has been selected as the English Misplaced Pages's ] (POTD) for December 30, 2023. A preview of the POTD is displayed below and can be edited at ]. For the greater benefit of readers, any potential improvements or maintenance that could benefit the quality of this article should be done before its scheduled appearance on the ]. If you have any concerns, please place a message at ]. Thank you! — ] (]) 13:32, 20 December 2023 (UTC) <!-- Template:UpcomingPOTD --> |
|
#Added bit on nyf, additional common forms |
|
|
|
<div style="margin-top:4px; border:1px solid #ddcef2; background:#faf5ff; overflow:auto;"><div style="margin:0.6em 0.4em 0.1em;">{{POTD/Day|2023-12-30|excludeheader=yes}}</div></div> |
|
#Added step-like to fracture description and elaborated on ''conchoidal'' |
|
|
#Added info on Australian blues coloured by hydrogen, qualifying instances of "natural blue" with "most" |
|
|
#Elaborated on Type IIa diamonds |
|
|
#Changed "play of color" to "fire." The term ''play of color'' correctly refers to ], not diamond. |
|
|
#Added to Symbolism subsection with a bit on LifeGem (I think it's interesting enough to mention). |
|
|
|
|
|
|
|
== Diamonds landscaping == |
|
This article could be expanded tremendously, but I'm ignorant as to exactly ''how'' extensive an article Wikipedians desire. ] 12:43, 8 Dec 2003 (UTC) |
|
|
|
|
|
|
|
Please advise employees to confirm w office before removing landscaping. Thx ] (]) 18:36, 10 May 2024 (UTC) |
|
What would you add? I'm no expert, but how about giving a list of suggestions here on the discussion page? Also, you could include extra details on different pages and link the main article to them. If it is generally felt they deserve to be in the main article someone will paste them across. --] 03:19, 1 Apr 2004 (UTC) |
|
|
|
|
|
---- |
|
|
===Is clarity grading done using a standard distance from eye-to-stone?=== |
|
|
|
|
|
Diamond clarity is graded on a scale from FL (flawless) to I (imperfect). |
|
|
The standards for each grade are based on how "obvious" or "difficult" it is to see imperfections at various magnifications, such as 1x (with the naked eye), 10x, or 30x. While on-line brochures give the magnification, they do not specify the distance between the eye and the stone. Is this 3"? (Probably not -- many people cannot focus this close.) Is this 6"? (Similar problem.) 14"? 15"? 21? Note that there is 3x magnification between 7" and 21". |
|
|
|
|
|
Do any of the major grading labs (such as GIA, AGS, or HRD) have a standard on this? For that matter, several ] (such as for surface defects in ceramics) have similar wording. Do the mil specs have a standard eye-to-object distance? |
|
|
|
|
|
:As far as I know, no. While I don't work for any of the labs you mention, I think I would have heard about such a standard. Nowadays most labs use custom microscopes for grading stones, so "distance to eye" doesn't come into play. A grader has to be careful not to scratch the objective lens with the stone, of course. |
|
|
|
|
|
:When a loupe is used, both it and the diamond are usually held fairly close to the eye as a matter of practice. When checking the stone with the naked eye (especially in unclear cases to judge whether an inclusion justifies a grade of I1 as opposed to SI2) a grader's astigmatism (or lack thereof) will determine distance from the eye. Although I'm fairly myopic and therefore I ''might'' be able to see closer, if I ''can'' see the inclusion the stone is automatically graded at least I1. (Visible to the eye means visible to the eye.) Some labs may assign an SI3 grade in debatable cases, but of course not everyone recognizes this grade. |
|
|
|
|
|
:Some labs are looser than others when grading stones, but that's not something I should get into here. I try not to be a mudslinger. ;) -- ] 04:30, 3 May 2004 (UTC) |
|
|
|
|
|
A few web sites address this question. They give various answers. |
|
|
|
|
|
* states that "I-1 I-2 I-3 (Imperfect)" diamonds "have inclusions that are eye-visible, viewed from the top (6 to 8 inches away)." |
|
|
|
|
|
* at PriceScope mentions 18 inches (for viewing the culet with the naked eye). |
|
|
|
|
|
* In a contentious 2002 on DiamondTalk, an appraiser is as saying, "Examining the stone loose for seeing unaided eye visible inclusion require the stone only being examined in the face up position approximately 15 inches from the eye and held in such a way that the table is perpendicular to the viewer's eye." |
|
|
|
|
|
Many microscopes have distances of 14-24 inches from eye-to-stone. |
|
|
Each microscope has a consistent distance for best viewing. |
|
|
|
|
|
:Heh, well.. as you can see, nobody can agree and there is no standard. I personally think both 18 and 15 inches is ridiculous. In the contentious DiamondTalk thread you linked to above, the buyer was clearly cheated. I can't believe someone would try to pass that stone off as anything better than an I1. (I can believe it, but you know what I mean.) I might have been meaner and went to I2, as a feather that large could conceivably affect the integrity of the stone itself. |
|
|
|
|
|
:Of all the links above, Bellman's would come closest to reason. There can't really be a standard, as human eyesight is so variable. That said, I did chuckle at this line from their site: |
|
|
|
|
|
::"Without the proper instruments and education on what to look for, consumers can easily misread a diamond’s clarity." |
|
|
|
|
|
:That may be true of the upper grades, but a savvy consumer should have no trouble spotting an I1, as the fellow in that DiamondTalk thread did. In my rather cynical opinion, I think sellers who use half a yard stick (for crying out loud!) to determine "eye visible" are trying to pass inferior stones off at higher prices than should be paid for them. And that bit about the culet was misinformation. A "medium" culet ''will'' detract from the final grade of the stone, or at least it should. As would a lack of culet in a large stone. |
|
|
|
|
|
:As for your comments on the microscopes, of course there is a consistent distance for best viewing. I don't think I understand what you're asking; maybe I'm daft, but how can a standard distance be applied to microscopes in this case? There are no great differences in the length of the optical train in the various models used (I've used at least three different makes). The distance from the stone and the objective lens would be determined by the magnification level. The only feature a microscope ''must'' have is a 10x setting (and, to be thorough, overhead lighting and darkfield illumination). Or am I missing something? -- ] 14:20, 10 May 2004 (UTC) |
|
|
|
|
|
Hadal, thank you for your straight answers. And no, you're not daft -- indeed, you have helped me clarify my thinking. |
|
|
|
|
|
"Or am I missing something?" |
|
|
|
|
|
I am trying to get at -- "What is 10x relative to?" |
|
|
*If you look through the microscope without the 10x lens in place, you will see the stone at 1x at a distance equal to the length of the optical train. |
|
|
*If you look through the microscope with the 10x lens in place, you will see the stone at 10x at the same distance. |
|
|
*Although I do not have access to a microscope, I remember the 10x-20x-30x microscopes used in several applications having very similar lengths of their optical trains. I remember it being somewhere between 14-24 inches, but cannot remember more exactly: |
|
|
**High school biology classes |
|
|
**Inspection of ceramics per U.S. Military specifications |
|
|
**Jewelry stores |
|
|
|
|
|
A couple of tangents: |
|
|
|
|
|
The current debate about cut-grading standards involves explicit assumptions about lighting and the distance at which a diamond is viewed. The choice of 10 inches versus 14 inches explains some significant differences between two proposed grading standards, according to this . |
|
|
|
|
|
By the way, the stone in the contentious DiamondTalk thread was graded by the AGS as an SI2. Perhaps large SI2 stones do not need to be eye-clean? |
|
|
|
|
|
-- ] 20:15, 14 May 2004 (UTC) |
|
|
|
|
|
---- |
|
|
To anyone who cares to sort such things out: |
|
|
|
|
|
The ] article seems to have three sections on color: |
|
|
* Optical properties |
|
|
* Composition and color |
|
|
* Color (in Diamond industry) |
|
|
---- |
|
|
Is "nyf" a word or an acronym? "gg:nyf mineral" turns up lots of mentions of NYF (niobium-yttrium-fluorine) ]. -] 05:09, 28 Jun 2004 (UTC) |
|
|
|
|
|
==Is diamond a Chemical element?== |
|
|
This article is recently added to the catagory of Chemical Elements. Carbon is an element, but are Diamond, Fullerene, Graphite elements??? |
|
|
|
|
|
:Diamond, fullerine, graphite etc. are not chemical elements. They are ] of the element carbon. I've deleted the flase category. Thanks for bringing this up. |
|
|
|
|
|
:] 01:19, 3 Aug 2004 (UTC) |
|
|
|
|
|
---- |
|
|
== various facts - insurance specific? == |
|
|
I'd add more, but the article being broken up into chunks and the slowness of my connection, in addition to[REDACTED] slowness makes this an issue. |
|
|
|
|
|
Needs: points (.01) as subsets of carats - plus add in a differentiation between karets and carats - plus carob bean reference. |
|
|
|
|
|
Carat weight, |
|
|
|
|
|
Cut (table, pavilion depth, crown angle) |
|
|
|
|
|
Diamonds take a high polish which enhances its scintillation. |
|
|
|
|
|
You can also test a diamond's light responsiveness |
|
|
|
|
|
Round brilliants are the most resistant to breakage, but a princess cut will give more caret weight per rough. A modified princess cut called the Arctic Empress (by Sirius) clips the vulnerable corners. Girdles on brilliants may be cut too thin as well. Pear cut and Marquise cut diamonds have sharp points which are vulnerable to damage. |
|
|
|
|
|
Most jewelry has a manufacturer/style number, since they are non-unique. |
|
|
|
|
|
Or to assure in writing that the stone is untreated. |
|
|
|
|
|
Many of these reports and serial numbers can or will be inscribed on the girdle, and some trademarks are making it to girdles (like the polar bear (under legal dispute) and the maple leaf). |
|
|
|
|
|
"Appraisal Reports" and "Identification Reports" offered by retail outlets are sales tools, and don't accurately reflect value, especially if they're selling you the item at significantly less than the appraised price. |
|
|
|
|
|
Treatments (and non-Treatments) |
|
|
* Laser Drilling (not required to disclose before 2001) - and interior acid washing of inclusions, sometimes filled with epoxy which can be damaged by repairing of the mounting when leaving the stone in place. |
|
|
* Coating - cleaning, recutting may damage the coating |
|
|
* Fracture Filling - heating, cleaning, resetting, recutting, can break down the treatment, exposing the original flawed stone. Often easy to detect. |
|
|
* Yehuda (Clarity) Treatment - a fracture filling treatment that injects resin. Not readily detectable by most jewelers, and not often disclosed (prior to 2001, it still may not be, depending on the honesty/knowledge of your jeweler). |
|
|
* Irradiation - Greens may breakdown on heating (cleaning, remounting). |
|
|
* Pegasus color treatment (Monarch) - General Electric inscribes the girdle of their treated stones with GE-POL, but some people have attempted to polish these off. Currently makes colorless diamonds, but they're moving toward fancies. No independent verification on how durable the treatment is. |
|
|
* EGL/NovaDiamond color enhancement - uses pressure and temperature to make fancies. No independent verification on how durable the treatment is. |
|
|
|
|
|
New FTC regs on treatments and disclosure to buyers |
|
|
|
|
|
Investment 'gems' and 'discounted' jewelry scams |
|
|
|
|
|
Dreseden Green Diamond, historical record to 1726, is being used to compare natural versus lab-produced irradiation in hopes of being able to devise a test to differentiat between the two. |
|
|
|
|
|
Lab Diamonds: |
|
|
|
|
|
(A process) developed by Gemesis, makes diamonds that may contain impurities in about 100 hours, by mimicing the natural process. |
|
|
|
|
|
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. |
|
|
|
|
|
Fake Diamonds: |
|
|
|
|
|
Cubic Zirconia - $5/carat - can get scratched, over time loses it's lustre, doesn't fool experts. |
|
|
|
|
|
Moissanite - $600/carat - almost as hard as diamond, more brilliant |
|
|
|
|
|
Beware of shipping items via mail, sometimes (US government, anthrax scare) irradiation is used, which can affect gems - most dramatically, cultured pearls, kunzite, and sapphire. Cumulative effects were also noted, even for the low level of irradiation used. |
|
|
|
|
|
Jewelry is routinely over-priced and then listed for 'discount', and it is buyer and insurer beware. Often the buyer pays for over-insurance, and the insurer is only obligated to pay for the replacement value - thus generating ill-will in all directions. |
|
|
|
|
|
Jewelers are anyone who sells jewelry. A jeweler can become a gemologist via a correspondence course. A graduate gemologist (GG) must take 6 months training, and includes hands on practical experience in a gem lab. Not all GGs know how to write an apprasial useful to insurance. |
|
|
|
|
|
:~ender 2004-09-04 MST 19:22 |
|
|
|
|
|
=== some statements that should have citations === |
|
|
|
|
|
Ender, these statements are interesting, and I would like to see references to learn more about them. -- ] |
|
|
|
|
|
Color (graded on D-Z, but composed of: Hue (31 gemstone grades), Saturation (9 grades), Tone (9 grades)) |
|
|
|
|
|
An ACORD (a non-profit organization for the insurance industry) 78/79 form certifies that the appraiser is a graduate gemologist of the Gemological Institute of America, has completed formal insurance appraisal training, examined the piece in a lab, all the qualities are as stated, there are no non-normal handling treatments of the stone, and that the appraiser is a professional who takes legal liability and responsibility for the apprasial, giving the insurer first party legal rights in the event of an error. |
|
|
|
|
|
* Does ACORD have a website? |
|
|
|
|
|
GIA reports are about $100 for a 1 carat diamond (minimum .23? carats) |
|
|
|
|
|
* The price information is subject to change without notice. Does it belong in the encyclopedia article? |
|
|
|
|
|
* If the GIA only grades stones above a minimum size, that might be worth including in the article. |
|
|
|
|
|
* Many vendors do not certify most of their small stones, especially under 0.50 carats. |
|
|
|
|
|
=== some statements where reasonable people may disagree === |
|
|
|
|
|
Clarity (IF,VVS1,VVS2,VS1,VS2,SI1,SI2,,I1,I2,I3) |
|
|
|
|
|
* As mentioned in the article, the SI3 grade is used by EGL-USA. Although it is not used by all laboratories, it is used enough in the diamond industry to appear on Rappaport price lists. |
|
|
|
|
|
(Various cuts with points or very thin girdles) may be uninsurable, or require much higher payments. should have issues with insurance due to inherent vice (legal term). |
|
|
|
|
|
* This depends on the insurance company, legal jurisdiction, and the fine print of the policy. |
|
|
|
|
|
A treatment which has broken down is not something for which an insurer is |
|
|
liable. |
|
|
|
|
|
* This depends on the insurance company, legal jurisdiction, and the fine print of the policy. |
|
|
|
|
|
AGS Diamond Quality Report (different from the AGS Diamond Quality Document) is considered the most complete and desirable report, contains all the information in the GIA report. It also includes information from the Sarin report, like the crown angle and pavilion depth, which are missing from the GIA report. |
|
|
|
|
|
* Unfortunately, the AGS' overall cut grade (e.g., AGS 0, AGS 1, etc) is still in its first draft, and is the subject of considerable controversy. |
|
|
* A number of discussions on , , and the first international cut conference are about possible improvements to the AGS cut grade. |
|
|
* The AGS has announced major changes to its cut grading. Many (perhaps most) stones that currently grade as AGS 0 will not grade as AGS 0 under the new standards. Many other stones that currently get lower cut grades will grade as AGS 0 under the new standards. |
|
|
* The new standards more closely align with computer simulations of cut quality, and with Tolkowsky's model of the crown. Unfortunately, the new standards have not been described in detail yet. |
|
|
* The AGS' new cut grading standards for round brilliants take effect in the first quarter of 2005. |
|
|
* The AGS also plans to issue cut grades for some fancy-cut diamonds. |
|
|
|
|
|
The Kimberley process has no independent verification, and is currently just a fig-leaf to cover the industry. |
|
|
|
|
|
* What is this "fig-leaf" trying to cover? |
|
|
|
|
|
(CVD diamonds) are said to be flawless in clarity. |
|
|
|
|
|
* Many industrial CVD diamonds are quite cheap. (About $1 per carat, for diamonds that are a few centimeters long and a fraction of a millimeter thick.) Unfortunately, many of these diamonds are golden-brown, like a well-done cake. |
|
|
|
|
|
(Cubic Zirconia) doesn't sparkle as much. |
|
|
|
|
|
* Perhaps some brands of cubic zirconia don't sparkle as much as ideal cut diamonds. Other brands cut to different proportions, or to more precise proportions, to make sparkly CZs. |
|
|
|
|
|
Branding is not considered worth insuring, and you can typically pay over 20% more for a conflict-free diamond. Insurers will not insure this extra value paid. The Insurer is responsible for repair or replacement of the actual stone, not the stone the customer may have thought he bought. |
|
|
|
|
|
* This depends on the insurance company, legal jurisdiction, appraisal, and the fine print of the policy. |
|
|
|
|
|
* Although most jewelry insurance policies are replacement policies, some insurance companies offer declared-value policies. |
|
|
|
|
|
* A few brands of diamond have special-enough cuts that some insurers have been convinced that a "like kind and quality" replacement should be made on a brand-name basis. In these cases, it was important that the brand-name information (or cut parameters) was disclosed to the insurance company in the appraisal. This has been discussed on . |
|
|
|
|
|
* The price premium for conflict-free diamonds is questionable. Part of the question is, "Which diamonds are really conflict-free?" |
|
|
|
|
|
(Moissanite) fools many professionals. |
|
|
|
|
|
* The gem laboratories have offered training to teach the differences between moissanite and diamond. |
|
|
|
|
|
Even judgements by the courts and the BBB have found it unfair to single out one retailer when deceptive practices are so widespread in the industry (JC Penny vs. NC) |
|
|
|
|
|
* A link to the ruling would be nice. Also, this depends on the jurisdiction. |
|
|
|
|
|
HTHP, developed by Gemesis |
|
|
|
|
|
* HTHP stands for High Temperature High Pressure. This adjective is used in other contexts (such as color treatments), besides lab-grown diamonds. |
|
|
* Many lab-grown gems (such as sapphires) are subjected to HTHP color treatments in addition to the process(es) used to grow the gem. |
|
|
|
|
|
== Old Mine cut == |
|
|
|
|
|
what is? |
|
|
|
|
|
] 09:17, 5 Sep 2004 (UTC) |
|
|
|
|
|
== Length == |
|
|
|
|
|
This article has gotten to be kind of an indigestible monster. I'm inclined to think that the "diamond industry" part would make a useful cutting point, or perhaps moving the fine points of quality to a sub-article. ] 13:57, 28 Oct 2004 (UTC) |
|
|
|
|
|
== Purchasing a diamond == |
|
|
|
|
|
I'd like to add a "Purchasing a diamond" section, to debunk some myths about diamonds and to help people into making a wise decision when shopping for a diamond. Do you think it should be part of this article, or a separate one? Anyone willing to pitch in? Reply here... ] 23:17, Dec 15, 2004 (UTC) |
|
|
:Go for it. I added the orignal "4C's" material and that should be moved to your new article/section. ] 04:10, 16 Dec 2004 (UTC) |
|
|
|
|
|
== Hardest Naturally Occurring Mineral? == |
|
|
|
|
|
I may be wrong, but is ] not harder than diamond...? |
|
|
|
|
|
''It would help if you could provide a source.'' |
|
|
|
|
|
''In general, the strength or hardness of a material '' |
|
|
''depends on the size of the sample, and the temperature and pressure.'' |
|
|
''If you measure the hardness of a sample with only 60 carbon atoms,'' |
|
|
''you may get very different results than if you measure the hardness'' |
|
|
''of a 1 carat sample (containing 10^22 carbon atoms).'' |
|
|
''For instance, a collection of molecules (each of which has 60 carbon atoms)'' |
|
|
''may be a liquid.'' |
|
|
''Whereas diamond is solid at ].'' |
|
|
|
|
|
''By the way, what is the melting point of ]?'' |
|
|
|
|
|
Unfortunately i am unable to find an Internet based source for this, but i have heard this from many sources, although they may be inaccurate. If anyone can help... |
|
|
|
|
|
:::The sources provided in the article presents a modified form of a fullerene, ultrahard fullerite, it may not be naturally occuring. What it does link to is an academic paper, which provides infromation that shows that the engineered substance can under these circumstances, scatch diamond. Though it is physically harder than diamond, Ultrahard fullerite is not made in meaningful enough quantities or avaible in these quantitis in order to be considered a naturally occuring material, if even a mineral. When larger quantities are avaible, we can learn if the microscopic hardness translates to a macroscopic hardness harder than diamond, something meaninful given the current industrial usages of diamonds. --02:19, 21 Jan 2005 (UTC) |
|
Wow, is this a bad article. The lead states:"Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen)." This is absolute rubbish. It isn't its "rigidity" that gives bulk diamond its impermeability (if that's what is meant by contamination). It is easy to "contaminate" a diamond CVD film with you name it. How big is the difference between contaminating a 1 inch cube (say) of pure iron vs. pure diamond? Not much. Ion implantation into (the near surface of) a diamond is also trivial. If the editors meant that NATURAL diamonds (on Earth) are typically quite pure, then SAY THAT! I suspect, but just an ignorant suspicion, that diamond must transition between impure high-carbon 'stuff' to the pure allotrope. I expect that at some point there's LOTS of contaminants in the nascent diamond. Aren't most natural diamonds black? What's that?? (the preceding is a digression, I'm ignorant on their natural occurrence.) There are so many FALSE statements in this article that it needs a total rewrite. There are many other bloopers but I don't have the patience to list them all. (For instance, did you know that hydrogen will leave an ash when burnt? No? Well, just read this article. When a diamond burns (in O2), any contaminants are left as ash. Ridiculous. (as is the assumption of complete combustion of the carbon) Another false claim is that diamond contains the most atoms per unit volume. (aside: at first, I thought the editor meant per unit cell volume!, not sure why s/he used the word "unit" since it doesn't add clarity (but it is not wrong)). Estimates of hydrogen density in the sun's core is ~10,000 kg/m^3, and without qualifying pressure and temperature the claim is likely false. I could go on...)40.142.183.146 (talk) 20:59, 20 August 2023 (UTC)
level-4 vital article is rated FA-class on Misplaced Pages's content assessment scale.
![[REDACTED]](https://u3vuiephb.global.ssl.fastly.net/File:Misplaced Pages-logo-v2.svg){kind=link}
.png)