Joined: Wed May 06, 2009 1:10 am Posts: 11 Location: France
I recently bought from a dealer in Thailand (very cheap) what was described as a "Green tiger-eye jade" bracelet. Upon asking for more details, he said he doesn't know exactly, but it is a "colored jade." Testing the bracelet, I get a spec. grav. of 2.45 and a RI of 1.776 . What could it be?
Joined: Mon Oct 17, 2005 10:56 am Posts: 6461 Location: The frozen north prairie :-/
Yeah, just looked again . The only other thing I can think of with the RI/SG range would be glass. I'm not the sharpest knife in the drawer, though, so perhaps someone else can be more helpful .
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Joined: Mon May 14, 2007 11:00 am Posts: 1133 Location: Monterey, CA
I would question whether your analytical results are correct. How did you determine the RI of the curved surface? Have you considered the sample might not be homogeneous—something like an organic polymer filled jadeite?
Joined: Wed May 06, 2009 1:10 am Posts: 11 Location: France
The bracelet is round, yes, but it is totally composed of flat surfaces in the 3-5mm range, which are difficult to see on the photo I attached. I got a good line. As far as organics or colouration is concerned, I've had the bracelet in acetone for at least 5 minutes - no attack of the bracelet, no colouration of the acetone.
Joined: Wed May 06, 2009 1:10 am Posts: 11 Location: France
The spot system wasn't necessary, as I maneged to carefully find one of the small flat surfaces. I measured at least 4 times around the bracelet, all readings consistently about 1.775 .
Joined: Wed Nov 15, 2006 9:44 pm Posts: 1079 Location: Washington State
What's that bracelet look like under a microscope ? All of the natural materials that I've seen looking like that will show some evidence of a granular crystalline nature when looked at closely and with transmitted lighting. I've never seen glass have that granular look. I would think that glass would be obvious under a microscope, particularly in the areas with a dramatic change in color.
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