tephroite
tephroite, olivine mineral found only in iron-manganese ore deposits and skarns and in metamorphosed manganese-rich sediments, such as those of Cornwall, Eng., and Franklin, N.J., in the United States. Tephroite (manganese silicate; Mn2SiO4) forms a solid solution series with the olivine fayalite in which iron completely replaces manganese in the molecular structure. For detailed physical properties, see olivine (table).
This article was most recently revised and updated by Amy Tikkanen.
Citation Information
Article Title:
tephroite
Website Name:
Encyclopaedia Britannica
Publisher:
Encyclopaedia Britannica, Inc.
Date Published:
07 January 2019
Access Date:
November 13, 2026