ROCK NEEDS TO BE IDENTIFIED..

[lrps]

Hi Everyone!!

I REALLY need help with this, since I am completely baffled about it…any advice or help would be verry appreciated!!

I have a piece of mineral, which I believe could be an uncut diamond. It is very hard, it has cleavages, it scratches glass, it is transparent to translucent, if I look through it against a bright light rainbow colours can been seen inside, it has about eight to nine sides but I could not find out the correct density, as the tests tend to give different results at different times. It varies from 3.5 to 3.9. I did the tests at home by myself so there is a possibility for inaccuracies. It weighs 101.8g. It even allows infrared light to pass through it. It takes the colour of the light. one of its surface is rough appearing crystallized. On its surface there are yellow spots and blemishes. Inside it looks honeycombed when shone against light, otherwise it appears clear.

I am not sure where should I take this to find out what exactly it is, as I do not feel comfortable about it.

I am attaching an image of the mineral for everyone to see.

I live in the uk, so if anyone knows any professional institution which identifies rough rocks, can you please advice me?

Priti

 

[perry]

Find a professional gemoligist. Your local jewerly stores and/or appraisers should be able to direct you to one.

Be prepared to pay for their services.

Perry

 

[Richard Sherwood]

You might consider submitting it to the GAGB Gem Testing Laboratory (Gemmological Association of Great Britain) for positive identification. A very reputable organization, which you wouldn't have to worry about.

Gem Testing Laboratory
27 Greville Street (Saffron Hill Entrance)
London
EC1N 8TN
UK

Tel: 020 7405 3351
Fax: 020 7831 9479

E-mail: [email protected]

 

[denverappraiser]

Gem-A (contact info in Richards post) should also be able to assist you in finding a qualified gemologist in your home community. They operate a highly respected school for gemology and they have graduates all over the country.

Another alternative is to grind your sample into a very fine powder and burn it over a high intensity flame. Examine the flame with a spectroscope for telltale emissions. You should end up with a pretty good idea of what it used to be....

Neil Beaty
Independent Appraisals in Denver

 

[lrps]

Hi Richard,

Thanks very much for the replies.

I have looked in to the website of the GAGB but it seems that they do not offer a service to the public directly unless I submit it through a jeweller. I am a bit sceptical about giving in my mineral to an independent jeweller after reading others experiences with identifiers who have damaged their stone.
I have had the stone for such a long time that it has become a part of my life now, and even if it identifies negative for a diamond , I do not want to risk having it damaged.

Could you please suggest some options that I could adopt to?


priti

 

[denverappraiser]

priti,

No compentent gemologist will use distructive tests, either the one I described above or the use of hardness probes to scratch the surface. It shouldn''t be difficult to find someone who will do it while you wait, while you watch and with no damage of any kind to the stone. Gem-a graduates who are trained in this will have the title F.G.A. after their name. Jewelry stores and jewelry appraisers in your area may be able to help you locate one.

Neil Beaty
Independent Appraisals in Denver

 

[lrps]

Hi Neil

Thank you for the info. indeed, I went to a local jewller( known to be the only specialist). He told me its not a diamond without any test whatsoever. he didnt even touch or examine the stone in any close manner. When I asked him what else it could be, he rudely replied "i don''t know what it is". I was very suprised how he reacted when we even asked him if it is a glass, he said "i dont know". when i spoke to other jewllers they suggested that i should go back to him because only he has the instrments to identify a diamond. now i realise i will have to search for someone with FGA as you suggested.

Thanks again

Priti

 

[Richard Sherwood]

Date: 1/2/2005 12:40:41 PM
Author: lrps

When I asked him what else it could be, he rudely replied ''i don''t know what it is''. I was very suprised how he reacted when we even asked him if it is a glass, he said ''i dont know''...

now i realise i will have to search for someone with FGA as you suggested.

Yes, someone with an FGA and some class...

 

[Richard Sherwood]

Priti, the specific gravity you determined (3.5-3.9) suggests clear topaz (3.53) or glass (2.3-4.5). Diamond is 3.52, but I don'' t think it''s likely to be diamond.

 

[MerKaBa]

You said the stone has cleavage......

Diamond has a step-like cleavage with distinct step-like lines.

Topaz typically has a flat cleavage and glass has a concoidal fracture which may be smooth.

You may be able to search on-line for images of diamond cleavage which may be of some help in determining what your stone is.

Richard''s suggestion of topaz and glass are good possibilities. I don''t know the SG of quartz off hand but that could be another possibility.

Best wishes

 

[Garry H (Cut Nut)]

quartz is too low 2.65

if you can scratch it with CZ that would be the easiest test to rule out topaz.

Also emerse it in cooking oil with the CZ and see which has the highest relief - shapest edges - diamond should be mre distinct than CZ.

 

[Garry H (Cut Nut)]

And many inexperianced jewelers have heat probes that go beep when the thing is not a diamond - but make sure it has good contact with some metal - the heat transmission testers assume the stone is set in jewellery.

In addition - diamond feels colder to touch (top lip) than glass or other minerals.

 

[oldminer]

Topaz is a very good possibility. Some diamond testers will make a diamond indication for topaz. I used to have a diamond tester that reliably could tell Aquamarine from Blue Topaz. It would beep for blue topaz, but not for Aqua(Beryl). It also would beep for corundum. It still functioned pretty well as a diamond tester, but its calibration was a bit off and it actually made it more useful. Too bad that company is no longer producing that model. My newest CZ tester, will not respond to Topaz or Corundum. Better technology proving itself less useful. An unusal scenario.

 

[lrps]

I checked the cleavages. Not flat nor smooth either but not yet sure if I am reading it right.

 

[lrps]

Garry, What does cz stands for?

 

[fortheloveofdiamonds]

cz = cubic zirconia