_Beryl._--A very hard mineral of much beauty when transparent. It occurs in hexagonal prisms, commonly of a green or bluish-green color, but also yellow, pink and white. It is a silicate of aluminum and glucinum. Beryls are very rich in colors.
_Bloodstone._--A green siliceous stone sprinkled with red jasper, whence the name.
_Cameo._--A figure cut in stone or shell that is composed of different colored layers. The value depends on the artistic merit of the engraved figure.
_Carbuncle._--A beautiful gem of a deep red color (with a mixture of scarlet), found in the East Indies. When held up to the sun it loses its deep tinge, and becomes of the color of a burning coal.
_Carnelian._--A variety of chalcedony, of a clear, deep red, flesh-red, or reddish-white color. It is moderately hard, capable of a good polish, and often used for seals. It is now used but little.
_Cat’s-eye._--A variety of quartz or chalcedony exhibiting opalescent reflections from within, like the eye of a cat. The name is given to other gems affording like effects, especially the chrysoberyl.
_Chalcedony._--A translucent variety of quartz, having usually a whitish color, and a luster nearly like wax.
_Dendrite._--A stone or mineral in which are branching figures, resembling shrubs or trees, produced by a foreign mineral, usually by an oxide of manganese, and the moss agate.
_Diamond._--A precious stone or gem excelling in brilliancy, beauty of prismatic colors, and remarkable for extreme hardness. It is found in many hues--green, rose, straw, yellow, etc.--but the straw-colored ones are the most common. The diamond is a native carbon, occurring in isometric crystals, often octahedrons, with rounded edges. It is the hardest substance known. Diamonds are said to be of the first water when very transparent, and of the second and third water as the transparency decreases.
_Diopside._--A crystallized variety of pyroxene (a silicate of lime and magnesia), of a clear, grayish-green color; also called mussite.
_Emerald._--A precious stone of a rich green color; it is the most valuable variety of beryl. (See beryl.)
_Epidote._--A mineral, commonly of a yellowish-green color, occurring granular, massive, columnar, and in crystals. It is a silicate of alumina, lime, and oxide of iron, or manganese.