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Identity HelpIdentify this crystal please!

10th Oct 2018 19:10 UTCGospel In

Hi all,

This crystal has a shiny surface. S. g is about 2.70. To determine the hardness I grinded this crystal against silicon carbide stone (9.5 hardness) in which both the crystal as wellas silicon carbide stone got abraded. So I take, the hardness would be around 9. A quartz could not scratch it. Good fluorescence under uv light. Indian origin.

10th Oct 2018 19:12 UTCGospel In

10th Oct 2018 20:56 UTCKevin Conroy Manager

Are you sure about the hardness and origin? I ask because it looks like beryllonite.

10th Oct 2018 21:40 UTCReiner Mielke Expert

Silicon carbide wheels are made of grains sintered ( or glued) together so you cannot say the stone is harder than the wheel. All you can say is that the stone is softer than the wheel. It looks like a piece of albite to me but without the correct hardness there are other possibilities.

11th Oct 2018 03:26 UTCGospel In

Origin is certainly right and it has no problem to scratch a window glass, knife, a quartz crystal and a vertified floor tile.

11th Oct 2018 05:26 UTCDoug Daniels

If it scratched quartz (you are absolutely certain it was a scratch?), then the hardness was about 7, maybe a bit more. Pushing it to 9.5 - highly unlikely, as there are few minerals (at least commonly available) that have that high a hardness. Another clue - the first photo seems to show some striations running in the long dimension.

11th Oct 2018 06:00 UTCGospel In

Yes I'm sure, and there are striations. The stone is quiet heavy for it's size to.

11th Oct 2018 08:47 UTCErik Vercammen Expert

2,70 is a very average density, the same as quartz and calcite. But if the stone is indeed denser (please, measure again) then it may be topaz (with Mohs hardness 8)

11th Oct 2018 10:06 UTCOlav Revheim Manager

I agree with Reiner, the striations (terminations?) on the right hand side of the first picture IMG_20181009_103907.jpg looks very much like albite.

Olav

11th Oct 2018 13:03 UTCReiner Mielke Expert

I can see no cleavage so it is possible that it is simply a piece of quartz and the striations are the imprint of a contact surface.

11th Oct 2018 14:15 UTCEdgars Endzelins

Based on striations and fracture my guess would be Danburite. SG seems within margins of error..

11th Oct 2018 15:01 UTCGospel In

Anymore guesses would be appreciated.that crystal is 65 gms.

11th Oct 2018 15:50 UTCSusan Robinson

I wouldn't grind the stone against the silicon carbide wheel again. Any obvious damage will decrease its value quickly.

11th Oct 2018 16:11 UTCGospel In

A few more closeup pics for better view under uv and sunlight.

11th Oct 2018 16:35 UTCScott Rider

If calculated correctly, I bet you this quartz, and like Reiner was saying, the striations may be a result of contacts with something. I have found super gemmy, oddly shaped crystals of quartz in pegmatites very much like this one in question (albeit they are smoky), and sometimes the vug is so narrow and restricted that only a couple faces are formed... I've found one smoky that almost looked just like a topaz crystal because of it being restricted inside the pocket it formed in, so you wouldn't see all the typical faces in those environments.

But, my first impression was phenacite. But the SG was too low for that, assuming it was calculated correctly... So I am sticking with quartz. And from experience, hardness is very unreliable factor, mainly because many people do not do the tests correctly.

11th Oct 2018 16:42 UTCReiner Mielke Expert

"Based on striations and fracture my guess would be Danburite. SG seems within margins of error.. " If danburite is in the margin of error then you need a better measurement system. I would test your SG system using a known mineral like a piece of quartz, that will tell you how reliable your measurements are and thus help to narrow the possibilities.

11th Oct 2018 17:35 UTCGospel In

You can rely on my sg readings, because I tried quartz, corundum, diamond in the same way and the readings more or less near to the accuracy. Hardness test is abit tricky I agree with that.

12th Oct 2018 00:13 UTCReiner Mielke Expert

How much more or less?

12th Oct 2018 01:54 UTCGospel In

.2 or .3

12th Oct 2018 02:02 UTCReiner Mielke Expert

With that sort of uncertainty the true SG could be anywhere between 2.4 and 3.0 so it could be danburite, quartz or even pollucite.

12th Oct 2018 02:17 UTCGospel In

Sorry I meant .02 or. 03

12th Oct 2018 12:35 UTCReiner Mielke Expert

That puts it very close to quartz (2.66) so that is what I would calling it. Also you are not seeing fluorescence just the violet light from your unfiltered lamp.

12th Oct 2018 18:27 UTCGospel In

Reiner, is that albite or quartz or daburite or pollucite.finally, what it could be among those 4 of your guess?

12th Oct 2018 18:53 UTCScott Rider

Gospel, do you know a more specific area of India this was found?

Indian miners and dealers are notorious for not putting exact locations on the specimens they find, whether it is to hide the locality or maybe they just don't know it came from. There is a LOT of land in the Himalaya's that could produce this type of gemmy crystal...

13th Oct 2018 03:22 UTCGospel In

The exact location is in Andhrapradesh state, India. But don't know the pinpoint area where it is actually found.

13th Oct 2018 04:00 UTCDoug Daniels

That is a help. Kinda like saying a specimen was found in, say, Arizona, U.S.A., rather than just in the U.S.A. Narrows the location down at least a little.

13th Oct 2018 05:17 UTCGospel In

Just asking out of curiosity, these type of crystals are of any value? Or just a collectors piece?

13th Oct 2018 12:46 UTCGospel In

Local gemologist think it's goshenite (beryl) and also he think it's a broken fragment.

13th Oct 2018 15:58 UTCReiner Mielke Expert

Beryl is possible if you can scratch quartz which you said it could. Either way it is not worth much.

15th Oct 2018 16:11 UTCScott Rider

It could certainly be goshenite, the fractures, striations, SG and hardness all point in that direction.

15th Oct 2018 18:07 UTCGospel In

I think so..

18th Oct 2018 05:32 UTCGospel In

There are tiny black pepper spots inside this crystal. May I know what are they and what causes it.

18th Oct 2018 14:16 UTCWayne Corwin

Probably tiny schorl(black tourmalines), they often form together.

18th Oct 2018 19:33 UTCGospel In

Led torch at the back.

19th Oct 2018 17:26 UTCDonald B Peck Expert

Gospel, we need more information , , ,how hard is it, can you measure its specific gravity? . . . Where is it from?

19th Oct 2018 17:59 UTCGospel In

I have already written about the origin and all, please check it

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