|
154
|
PRECIOUS STONES
|
||
|
|
|||
|
Carnelian ..........Translucent; yellow, brown, or red;
color is deepened by several weeks' exposure to the sun's rays.
Cat's-Eye ...........Gray and greenish gray; translucent;
chatoyant when cut en cabochon, due to fibres of asbestos or actino-lite.
Chalcedony .........Clouded or translucent white, yellow,
pale brown, or blue, with a glistening or waxy lustre.
Chrysoprase.........Translucent, pale bluish or yellowish green variety of chalcedony; color is due to oxide of nickel.
Heliotrope ..........Bloodstone.
Jasper ..............Impure opaque, colored quartz; red,
yellow, brown, gray, sometimes blue. Called ribbon jasper when striped. Egyptian jasper is of a dead yellow running to brown.
Onyx ...............Is like agate with colors arranged in
parallel strata.
Plasma .............Faintly translucent; various greens,
sprinkled with yellow and whitish dots.
Prase ...............Translucent; deep green (supposed
to be colored by a trace of iron).
Rose Quartz.........Pink, sometimes opalescent. Fades
on exposure to light, but may sometimes be restored by leaving it in a moist place.
Sapphirine..........Or siderite. Translucent; grayish
blue, indigo, and Berlin blue.
Sard ................Light to dark brown-red.
Sardonyx ...........Sard with underlying parallel strata
of color.
|
|||
|
|
|||