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Inclusions in Purple Spinel
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Author:  Robin Winter [ Sat Nov 22, 2014 10:42 pm ]
Post subject:  Inclusions in Purple Spinel

Okie, so I've done some very basic testing and there's a good chance this actually is spinel, the S.G. was in range at 3.57, no noticeable magnetic response with a neodymium magnet so garnet is out and taaffeite is less likely than spinel. I wanted to see if anyone could offer insight on the inclusions. The pictures aren't great, but for the equipment I have, this is the best of what I could manage. The red/orange piece also looks black with a metallic/oily look when viewed from other angles. There are what appear to be very tiny different colored crystals around the inclusion mass but I couldn't capture those, and the white/clear mass has a weak rainbow effect across it in areas in good light. There's also one bubble shaped inclusion that's too small to see without good magnification that has a tiny little black dot in the middle, just outside the main mass.

Just a note, the lines at the bottom in the first picture are on the surface, the polish on this stone was garbage.

Image
Image

Author:  GSK [ Wed Mar 04, 2015 10:19 pm ]
Post subject:  Re: Inclusions in Purple Spinel

A bit time passed for the reply.. :)

Do you know origin of this spinel?

My suggestion - the black spot in spinel might be metamict zircon or, even more chances - uraninite crystals, also graphite is possible. Brown crystal with surraunded stress cracks - magnetite, it is actually black and often appears metallic greyish brown under bright reflected light.

Author:  Robin Winter [ Thu Mar 05, 2015 12:36 pm ]
Post subject:  Re: Inclusions in Purple Spinel

Supposed to be Tanzania. Thanks for the reply :)

Author:  dstojan [ Thu Mar 05, 2015 1:28 pm ]
Post subject:  Re: Inclusions in Purple Spinel

Oh and I think taaeffite is double refractive and spinel is not so you could probably easily rule out that!

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