Sillimanite is an aluminum silicate, related to both andalusite and kyanite. In fact these three minerals are polymorphs - they share the same chemical composition but different crystal structures.

Sillimanite is named after the American chemist Benjamin Silliman (1779-1864). Silliman was one of the first American professors of science and taught at Yale University.

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buy a few items every year. Site is easy to use and selection is virtually unlimited. Easy to use and, tho I have no real basis for comparison, prices seem reasonable.

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I'd say that the information in the descriptions is rather sparse, and the state of the gems/their color treatment or lack thereof is vague and unimpressive. Nevertheless they've got a great variety of offerings. The only area I can see that they could improve is in turquoise, which could include unstabilised cabs or at least specific names relative to their mines as opposed to appearances. Thanks

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Overall Rating -> 10

I purchased another kyanite'the intense color saturation of this stone is incredible. The quality was as described and pictured in the photos. Always happy with my purchases!

Posted By Greyghostnh in March, 2021

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