About Sillimanite Cat’s Eye
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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