ripidolite

from The Century Dictionary.

• noun The commonest member of the chlorite family of minerals, occurring in monoclinic crystals with micaceous cleavage, also scaly and granular, usually of a deep-green color, rarely rose-red. It is a hydrous silicate of aluminium and magnesium. Also called clinochlore.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Min.) A translucent mineral of a green color and micaceous structure, belonging to the chlorite group; a hydrous silicate of alumina, magnesia, and iron; -- called also clinochlore.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun mineralogy A translucent green chlorite mineral of micaceous structure; a hydrous silicate of alumina, magnesia, and iron.