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.

Certified Customer Reviews

Overall Rating -> 10

This website is just ballin!

Posted By Thebigballer in December, 2020

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Overall Rating -> 10

I love the layout of the website and their selection! the quality of their gems is unlike any other I have seen!

Posted By Matty in July, 2021

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Overall Rating -> 10

ease of going through site and making purchase. will update when item received

Posted By CAT in July, 2021

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Overall Rating -> 10

I had a limited budget and wanted a star ruby. GemSelect offered small, but pretty stones at a very reasonable price. I've always been satisfied with my GemSelect purchases, although there are also eBay vendors I use for less expensive gems. Their selection of more expensive stones, like rubies, is very limited, however.

Posted By Dr S in February, 2021

Source: Bizrate

Overall Rating -> 10

Completely would recommend this company to any gem collector, jewelry store, or someone looking for a gemstone to repair their jewelry. There is an abundance of choices at great prices! If you dona't see what you need exactly the customer service department will go above and beyond to meet your needs. Shipping is very reasonable! The gemstones always arrive well before the expected arrival date. This company has very high standards of meeting their customers needs! They are the number 1 company I go to when looking for any gemstone. They are also very detailed in their descriptions so there is no confusion at all as what you are purchasing! Highly recommended!!!!

Posted By Cliff in July, 2021

Source: Bizrate

Overall Rating -> 10

I was pleased with the amount of information they offered along with the accuracy of such information. Navigating their website was effortless as well. Although, I wish they had a wider variety in a particular gemstone, I was satisfied overall.

Posted By RCM in January, 2021

Source: Bizrate

Overall Rating -> 8

Its a great place to get quality Gems for a great price.

Posted By Kenny in April, 2021

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Overall Rating -> 10

First time buying from this company. I hope it was definitely worth it because I am extremely nervous.

Posted By Non in June, 2021

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Overall Rating -> 9

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.

Posted By Jim in March, 2021

Source: Bizrate

Overall Rating -> 9

It is amazing to see the vast quantity of gemstones available in a wide variety of sizes and at a variety of price points. Overall GemSelect is a stellar place to find that perfect gem

Posted By Ty in August, 2021

Source: Bizrate

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