cummingtonite
cummingtonite, an amphibole mineral, an iron and magnesium silicate that occurs in metamorphic rocks. For chemical formula and detailed physical properties, see amphibole (table).
This article was most recently revised and updated by Amy Tikkanen.
Citation Information
Article Title:
cummingtonite
Website Name:
Encyclopaedia Britannica
Publisher:
Encyclopaedia Britannica, Inc.
Date Published:
03 August 2026
Access Date:
November 14, 2026