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Identify this crystal please!

Posted by Gospel In  
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Gospel In October 10, 2018 07:10PM
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.




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Gospel In October 10, 2018 07:12PM

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Kevin Conroy October 10, 2018 08:56PM
Are you sure about the hardness and origin? I ask because it looks like beryllonite.
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Reiner Mielke October 10, 2018 09:40PM
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.
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Gospel In October 11, 2018 03:26AM
Origin is certainly right and it has no problem to scratch a window glass, knife, a quartz crystal and a vertified floor tile.
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Doug Daniels October 11, 2018 05:26AM
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.
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Gospel In October 11, 2018 06:00AM
Yes I'm sure, and there are striations. The stone is quiet heavy for it's size to.
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Erik Vercammen October 11, 2018 08:47AM
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)
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Olav Revheim October 11, 2018 10:06AM
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
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Reiner Mielke October 11, 2018 01:03PM
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.
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Edgars Endzelins October 11, 2018 02:15PM
Based on striations and fracture my guess would be Danburite. SG seems within margins of error..
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Gospel In October 11, 2018 03:01PM
Anymore guesses would be appreciated.that crystal is 65 gms.



Edited 1 time(s). Last edit at 10/11/2018 03:04PM by Gospel In.
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Susan Robinson October 11, 2018 03:50PM
I wouldn't grind the stone against the silicon carbide wheel again. Any obvious damage will decrease its value quickly.
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Gospel In October 11, 2018 04:11PM
A few more closeup pics for better view under uv and sunlight.




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Scott Rider October 11, 2018 04:35PM
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.



Edited 1 time(s). Last edit at 10/11/2018 04:35PM by Scott Rider.
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Reiner Mielke October 11, 2018 04:42PM
"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.
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Gospel In October 11, 2018 05:35PM
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.
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Reiner Mielke October 12, 2018 12:13AM
How much more or less?
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Gospel In October 12, 2018 01:54AM
.2 or .3
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Reiner Mielke October 12, 2018 02:02AM
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.
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Gospel In October 12, 2018 02:17AM
Sorry I meant .02 or. 03
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Reiner Mielke October 12, 2018 12:35PM
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.
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Gospel In October 12, 2018 06:27PM
Reiner, is that albite or quartz or daburite or pollucite.finally, what it could be among those 4 of your guess?
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Scott Rider October 12, 2018 06:53PM
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...
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Gospel In October 13, 2018 03:22AM
The exact location is in Andhrapradesh state, India. But don't know the pinpoint area where it is actually found.
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Doug Daniels October 13, 2018 04:00AM
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.
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Gospel In October 13, 2018 05:17AM
Just asking out of curiosity, these type of crystals are of any value? Or just a collectors piece?
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Gospel In October 13, 2018 12:46PM
Local gemologist think it's goshenite (beryl) and also he think it's a broken fragment.
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Reiner Mielke October 13, 2018 03:58PM
Beryl is possible if you can scratch quartz which you said it could. Either way it is not worth much.
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Scott Rider October 15, 2018 04:11PM
It could certainly be goshenite, the fractures, striations, SG and hardness all point in that direction.
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Gospel In October 15, 2018 06:07PM
I think so..
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Gospel In October 18, 2018 05:32AM
There are tiny black pepper spots inside this crystal. May I know what are they and what causes it.
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Wayne Corwin October 18, 2018 02:16PM
Probably tiny schorl(black tourmalines), they often form together.
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Gospel In October 18, 2018 07:33PM



Led torch at the back.



Edited 1 time(s). Last edit at 10/18/2018 07:34PM by Gospel In.
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Donald B Peck October 19, 2018 05:26PM
Gospel, we need more information , , ,how hard is it, can you measure its specific gravity? . . . Where is it from?
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Gospel In October 19, 2018 05:59PM
I have already written about the origin and all, please check it
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