An aluminosilicate mineral typically occurring as fibrous masses, commonly in schist or gneiss.‘Muscovite and aluminosilicates are almost entirely absent although, where present, the aluminosilicate is sillimanite.’
- ‘The aluminium silicate minerals andalusite, kyanite, and sillimanite are good examples of this phenomenon of polymorphism.’
- ‘Growth of titanite took place during the metamorphic climax in rocks from the kyanite and sillimanite zones.’
- ‘Kyanite and sillimanite may also be present but only as minor components.’
- ‘The country rock was regionally metamorphosed to above the sillimanite isograde.’
Mid 19th century from the name of Benjamin Silliman (1779–1864), American chemist + -ite.
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