astrophyllite

[In Ger. astrophyllit; Gr. ἄστρον (astron) = a star, and φύλλον ( phullon ) = a leaf.] Min.: An orthorhombic mineral cla ed by Dana under his Mica Group. The hardne is 3; the sp. gr., 3-324; the lustre, sub-metallic, pearly; the colour, bronze-yellow to gold yellow. It is translucent in thin plates. Composition: Silica, 32-21 to 3371; protoxide of iron, 18:06 to 25-21; protoxide of manganese, 9.90 to 12-68; titanic acid, 709 to 8-84, with le er quantities of pota a, soda, zirconia, alumina, and other ingredients. It is found in Norway.