The Collaborative International Dictionary
cronstedtite \cron"stedt*ite\ (kr[o^]n"st[e^]t*[imac]t), n. (Min.) A mineral consisting principally of silicate of iron, and crystallizing in hexagonal prisms with perfect basal cleavage; -- so named from the Swedish mineralogist Cronstedt.
Wiktionary
n. (context mineral English) A trigonal-ditrigonal pyramidal mineral containing hydrogen, iron, oxygen, and silicon.
Wikipedia
Cronstedtite is a complex iron silicate mineral belonging to the serpentine group of minerals. It has a formula of FeFe(Si,FeO)(OH).
It was discovered in 1821 and named in honor of Swedish mineralogist Axel Fredrik Cronstedt (1722–1765). It has been found in Bohemia in the Czech Republic and in Cornwall, England.
Cronstedtite is a major constituent of CM chondrites, a carbonaceous chondrite group exhibiting varying degrees of aqueous alteration. Cronstedtite abundance decreases with increasing alteration.
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Cronstedtite- Cornwall, England
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