What is 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 called?

ripidolite — 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. (Webster's 1913.)

Sources