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Odd Kashmir Sapphire

I have a .30 carat Kashmiri Sapphire that I have had for ages. It is quite dark and I just had it under the microscope for the first time under 100 power. The color zoning is nice and I can see real fine silk. But I can also see some dark staining ON the stone in small spots. I have soaked it in a serious cleaner that cleans just about anything. They are still there. Could this stone have been dyed? Well I’d this is so how would I remove the dye! There is no dye in the microscopic chips or cutting lines in the stone. Could these be some kind of flaw? I do not have capability of taking pictures of what I see through my scope. I could drop it and try to polish it and see what happens. I do have fine diamond finishing polishes. The stone was given to me for study. Any suggestions would be greatly appreciated.
All the very best!
Otter

Hi Otter, wondering if Heat treating the sapphire may help??? will certainly get rid of the rutile needles and may brighten up the gem

SydP,
The rutile I can see in this stone is more like silk and is very fine. I was looking at the stone under 100 power magnification. The odd part is the small dark spots and splots. I think the stone was dyed but I can not understand it being dyed so dark. I will take a picture of it in the daylight tomorrow and post it then.
Otter

Without a photo, my guess would be polishing compound/swarf residue that became forced into surface reaching defects during polishing. Since sapphire would almost invariably be polished with diamond compound and lubricant, black swarf could easily be forced into any fissures. I have had this happen with peridot, and thought for sure I had black spots ON my stone, but they were really just subsurface. This effect is well known with emerald, and is why the stones are often boiled in acid after polishing.

Sorry, don’t mean to be curt to the readers here, not my intention.

Otto why do you say your sapphire is Kashmir in origin? Was it sold to you this way, and/or did it have a report? Kashmir sapphires are typically not dark, and do not have silky rutile in them. Not part of their geological makeup.

Heat treatment of a Kashmir sapphire, while it has been done, would most likely ruin the stone… and devalue it.

RE: “This effect is well known with emerald, and is why the stones are often boiled in acid after polishing.” Please never do that to an emerald. :skull_and_crossbones:

All IMHO,
Bear

I did mis speak when I said rutiles. I strictly meant silk in the stone.
Forgive me for the confusions.
All the best to y’all,
Otter

Hi see attached report on Kashmir Sapphires

sounds like its died that mine has been depleted for so long to my knowledge i bought hundreds of dollars of this type of rough all dark and died i got ripped off

My late husband bought this for me back in the early '80’s of that helps any. I was going to set it in a ring but never got around to it. He got it at a reputable dealer that we have known for years that was GIA certified but he never go around to certifying it for him. He said that it was a good stone so he believed him. I had forgotten all about it till recently. Thanks for all of the input.
All the best y’all,
Otter