Dictionary
am•phi•bole
Pronunciation: (am'fu-bōl"), [key]—
n. Mineral.
any of a complex group of hydrous silicate minerals, containing chiefly calcium, magnesium, sodium, iron, and aluminum, and including hornblende, tremolite, asbestos, etc., occurring as important constituents of many rocks.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.