Talk:Diamond/Archive 4

message: lonsdaleite not a diamond form. That is anoather mineral and inother allotrop of carbon. Stepanovas 11:49, 4 Jun 2005 (UTC)
replies: text: While lonsdaleite is indeed IMA-approved as a distinct species, AFAIK it isn't entirely incorrect to call it a form of diamond. It's my understanding that lonsdaleite is a polymorph of diamond rather than a proper allotrope in itself, as unlike graphite and fullerene, there are no differences in the chemical bonding between diamond and lonsdaleite (rather, the differences relate to physical arrangement only). Then again, I could be wrong; furthermore, from what I've read, the exact definition of allotrope vs. polymorph isn't quite settled yet. Would it help if "form" were changed to "polymorph" for greater clarity? (By the way, did my edits to the Surfacing section resolve your concerns with respect to indicator minerals present in diamondiferous kimberlites?) -- Hadal 02:54, 5 Jun 2005 (UTC)
replies: text:  By definition structure is a main characteristic of mineral and substances with different structures can not be the same mineral. Surfacing section became mach better, but there are still a lot of mistakes Stepanovas 13:07, 6 Jun 2005 (UTC)
replies: text: I think there may be a language barrier here. Nobody has suggested lonsdaleite and diamond are the same mineral; rather, that they are polymorphs of each other. In other words, they are two forms of the same carbon allotrope. To prevent the possibility of someone confusing "form" to mean "variety" (as seems to be the case here), I've gone ahead and rewrote the paragraph to make lonsdaleite's relationship with diamond clearer. As for the Surfacing section, what precisely are these mistakes? You're not the first geologist to read the article, but if there's something you think we've missed, I encourage you to elaborate. Simply saying, "... there are still a lot of mistakes" isn't very helpful. (If you're not comfortable editing the article yourself, the only way to address your concerns is for you to explain them in detail.) Note that some of the geophysical concepts may be simplified to make them more accessible to the general public; this does not, however, mean the text is wrong. -- Hadal 02:37, 7 Jun 2005 (UTC)
replies: text: Stepanovas 07:03, 7 Jun 2005 (UTC)
replies: text: Everything I've read (save for Wikipedia's own contradictions) describes lonsdaleite as a polymorph of diamond's allotrope rather than a different allotrope; in the absence of evidence to the contrary, I think the wording should stay the way it is. (I do appreciate the murky ground we're treading here, but as Wikipedia is meant to report rather than dictate, we should be careful not to contradict our references.) As for lamproite/lamprophyre, I am in complete agreement (I didn't write that part and didn't notice the piped link). I didn't write the serpentine bit either, but if you know what to replace it with, by all means do so. As for the Ti issue, my reference for that is the one I supplied in the same edit (Kjarsgaard and Levinson 2002). The article is primarily on Canadian diamond prospecting, but its background information is generalized. "Cr-spinel" and "Ti-pyrope" are both specifically mentioned; as is picroilmenite (another titanium compound), hence "or titanium". Both transition elements, both resulting in strong colours. The referenced article clearly distinguishes eclogitic garnets from the "Ti-pyrope" (as does this article), so although both are orange, that does not mean both lack Ti. -- Hadal 02:09, 8 Jun 2005 (UTC)
thread_title: lonsdaleite

message: These diamond dealers have photos of chipped diamonds to prove that diamonds are more easily damaged than you might think.  Also they claim that a diamond can be scratched with metal.  "Can Diamonds Be Chipped?"  61.229.142.233 08:08, 12 Jun 2005 (UTC)
replies: text: Chips are one thing; the "Mechanical properties" section—and its corresponding subarticle material properties of diamond—make it clear that diamond is fragile and that fracture/cleavage is a real danger. As for the claim that diamond can be scratched by "a pop-top from a soda can", that's certainly false. If diamond could be abraded by aluminium, steel, or even corundum, it wouldn't have taken hundreds of years to develop diamond cutting methods. If any marks are left on a diamond by metal, they could be either (a) residue of the metal itself, or (b) very fine hairline cleavages, known as "bearding" when they occur along the girdle. The site you link to illustrates quite well that you shouldn't believe  everything your dealer tells you. -- Hadal 03:15, 13 Jun 2005 (UTC)
thread_title: Can't be scratched?

message: I came to this page looking for links to some famous diamonds - e.g. the Hope diamond, and I noticed that there isn't anything like that on the page. It's out of my depth for me to attempt anything like that, but I was wondering if anyone else thought that sort of thing would be appropriate for the page. I know I'd like to see it here. - MrCheshire
:Actually, there is already a link to list of famous diamonds indented at the bottom of the ==History== section. The list was calved off into its own article in order to keep the main article's size down. I do see how the link could be easy to miss; it was repeated again under ==See also==, but I believe it was removed some time ago as being "redundant". Although it might be possible to summarize (rather than list) the many famous diamonds to create a ==Famous diamonds== section, I think this would be better accomplished by turning the list article into a "famous diamonds" article, simply because the main article is large enough as it is. Does that make sense? -- Hadal 08:29, 16 Jun 2005 (UTC)
thread_title:  Additional section? 

message: How about a sentence on the largest diamond ever found the Cullinan Diamond? I think it would be interesting as well as providing a size range eg diamonds range from x to X Carats.
Ravedave 06:13, 17 July 2005 (UTC)
replies: text: I added such a section. I think it gives the most important information without turning into a list, but feel free to tweak it of course. —Keenan Pepper 21:14, 5 November 2005 (UTC)
thread_title:  Largest Diamond? 

message: The article here says that diamond is highly electronegative. Could someone confirm and then add it to the article? It would be useful to go into why diamond being electronegative would be a useful property.--ShaunMacPherson 02:26, 13 September 2005 (UTC)
thread_title:  Diamond is [[electronegativity|electronegative]]?