chloropal

Definitions

A massive mineral, greenish in colour and opal-like in appearance, essentially a hydrous silicate of iron.

Examples

“A careful consideration of the various analyses of minerals of the chloropal group given by Dana, leads me, therefore, to propose⟳ that the following species and varieties should be regarded as a series of types to which all future discoveries in the group may be referred.”

“Several delessites and chloropals occurring in basalts have⟳ a composition very close⟳ to that of the glass.”

“Nontronite, a variety of chloropal occurs as a light⟳ yellow powder in druses of the North Conway granite (99, p. 312).”

CEFR level