| Silica | 52.9 |
| Alumina | 30.3 |
| Lime | 12.3 |
| Soda | 4.5 |
Large masses of this stone are found on the coast of Labrador. It is also found in Finland, Russia, and the United States. Because of the dark chatoyant appearance the name of œil de bœuf or ox-eye is sometimes applied to labradorite. Handsome specimens, cut cabochon, form pretty ring stones, and many effective engraved cameos have been produced by using the bright portion for the relief work and the gray dead part for the base.
Cyanite.
This stone is the transparent variety of disthene, and is sometimes commercially known as sappare. Cyanite is colorless to bluish-white, sky-blue, berlin blue, yellowish- and reddish-white, gray, and green.
The hardness is 5 to 7, specific gravity 3.45 to 3.70, lustre vitreous and pearly; it is infusible before the blow-pipe, but fuses with borax; is not attacked by acids, and is composed of:
| Silica | 36.8 |
| Alumina | 63.2 |
Cyanite is found in Switzerland, the Tyrol, Styria, Carinthia, Bohemia, Norway, Finland, France, South America, Scotland, Ireland, Siberia, the East Indies, and the United States. Clean specimens are not plentiful, and fine blue pieces have frequently been sold for sapphires. The cyanite can be distinguished from the sapphire by its inferior hardness and lighter weight.
Lapis Lazuli.
Lapis lazuli, the sapphire of the ancients, is a mineral, translucent to opaque, ranging in color from colorless to an azure-blue, violet-blue, green, and red.
The principal color, however, is a rich, azure blue, sometimes shading into green, and having a vitreous to greasy lustre.