Chloropal

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).