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Please help me identify this globular purple crystal.

0 votes
https://flic.kr/p/tTTbKG

https://flic.kr/p/ubD2qt

The encrusted spot in the middle right of the second picture looks like quartz, but through a loupe it had alot of 5 sided crystals with flat terminations.

The greenish crystal seems to be between 3.5 - 5.5 hardness (apatite?) The purple seems a bit harder, but it was hard to tell due to the size and encrusted surface. This came from an old family collection and was probably found in or around Grand County, Colorado.

Edit: Non-fluorescent, and the location could possibly include Arizona.

Edit 2: Found a bigger piece of this same rock https://www.flickr.com/photos/128269620@N04/shares/8FQ555
asked Jun 5, 2015 by HappyDigger (220 points)
edited Jun 10, 2015 by HappyDigger

1 Answer

0 votes
Several possibilities come to mind. The strongest one is smithsonite, other idea is fluorite. Can you get a picture of the matrix. Also can you do an acid test to rule out the carbonates?
answered Jun 9, 2015 by hershel (46,480 points)
I am not sure about the matrix, the whole thing is a mass of different crystal formations. I did add some photos of bigger piece of that rock. I tested with vinegar 5% (is that strong enough?), and did not see any reactions on any of the crystals or the small amounts of white matrix looking rock.
Calcite is very sensitive even to weak acids like vinegar, but to really test this use a strong acid like lime out in a medicine dropper. If it doesn't react to that you can rule out the carbonates.
Ok, thank you very much for all the info. Tested with lime away pro strength and still no reactions on the crystals or matrix.
 


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