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 Post subject: Looking to identify this crystal rock
PostPosted: Tue Apr 21, 2020 8:56 pm 
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Hello,

Do any experts know what kind of crystal rock this is? I have had it for years and have not been able
to find out what it is. It is like a quarts crystal but is shaped differently. I feel they are very similar to Tetragonal shape but flat on top and Orthorhombic shape. Not sure if any of that helps. Thank you so much for your help.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 5:27 am 
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Looks like mica.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 11:22 am 
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Location: Belgium
My guess : baryte. Check the hardness and the density.

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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 2:27 pm 
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Let's have a little more information.
Hardness?
Cleavage or fracture?
Scratch test?


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 3:22 pm 
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Thank you marcm and Dioptase for your reply. I really appreciate it.

marcm
Quote:
Check the hardness and the density.
Thank you for your suggestion. Forgive me I am not educated in these kinds of things. I did google your suggestion and got some understanding of what you meant. I am not sure if I got the right information on that but it does look very complicated. At least for me.

I will share the weight and measurement of it, not sure if that helps.
The crystal weighs 7.9 lbs, with a circumference of 21 1/2 inches, 6 1/2 inches at it's tallest point and is 9 1/4 inches across the length of the crystal. There is no "rock" looking material that I can see in the piece except for a very small one on the bottom. The rest of it consists of crystals in various sizes throughout the piece.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 3:28 pm 
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Hello Barbra,

Thank you for your reply. Forgive me I am not educated in these kinds of things. I don't know how to do any of those things.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 5:11 pm 
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After watching the videos in the "How to help identify minerals" section of the forum I was able to determine the Hardness - Cleavage or fracture and Scratch test.

Cleavage or fracture? I found breaking off small pieces from the bottom of the specimen they look to be Cleavage.

Hardness? Testing for hardness was very interesting because in some areas of the side and bottom of the specimen scratched glass but the top main area of the specimen it did not scatch the glass. I then tried a penny and it was very similar to the glass scratch test. On the Moh's scale, I would say it is under 3 in some areas mainly the top and above 5.5 in other areas of the specimen, the bottom and sides areas scratched the penny. The areas that did not scatch the glass or penny left behind a powdery streak on the surface which of course worn down the edge of the specimen piece. I was able to see this much clearer on the penny.

Also after a close inspection of this specimen (we well just call it that now), I notice looking at it under a very high magnifier I saw some gold-colored areas, which look like pyrite. The clusters on the top of the specimen have a rainbow effect inside them when I shine a light on them.

hope that helps.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Wed Apr 22, 2020 10:56 pm 
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Look at you go.
Well done!
I am not seeing mica, nor baryte here.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Thu Apr 23, 2020 5:19 pm 
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marcm wrote:
My guess : baryte. Check the hardness and the density.


Yup, that was my first guess, too.


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 Post subject: Re: Looking to identify this crystal rock
PostPosted: Fri Apr 24, 2020 4:15 pm 
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thank you Barbra, I hoped that helped. I am still researching this specimen, but I am stumped. It does not seem to be baryte or mica in relation to identifying in pictures either as far as I have found. I marked out in red some areas of the specimen's Crystal Forms in a new photo. I also included a photo of the rainbow effect when light is directed at it. The color is blue/grey and darker almost to black as you can see in the pictures. I am going to test it again I may have done the test incorrectly. I thought the mineral fragments or powder when testing was a clear indication it did not produce a scratch. I did not check for a scatch after wiping away the mineral fragments or powder. I will test again. Oh, and I would also like to share that this specimen came from the Rock Candy Mine in British Columbia, Canada. It was given to me by a friend around 1984.

Thank you dchallener. :)


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