180 PRECIOUS STONES
easy
in one direction, showing a lined surface. Composition: silica, 52;
lime, 48. Fuses with difficulty to colorless glass; with borax, to
transparent glass. Color, white to yellowish pink or brown.
Zoisite
is a variety of epidote, with two to nine per cent, of oxide of iron.
The prisms are often striated longitudinally. The name was given
originally to the epidote of grayish or hair brown, but
yellowish-brown and greenish-gray crystals have been found in
Tennessee, and rose-red in Pennsylvania. The finest come from Norway.
It fuses on the edges and swells up before the blow-pipe, but does not
liquefy. Hardness, 6 to 7; specific gravity, 3.25 to 3.46; brittle.
Lustre vitreous; translucent to opaque.
Zonochlorite is a banded green stone, from which appearance its name was taken. It is found in the Lake Superior region.