LAZ'ULI . Lapis lazuli is a mineral of a fine, azure blue color, usually amorphous, or in rounded masses of a moderate size. It is often marked by yellow spots or veins of sulphuret of iron, and is much valued for ornamental work. It is distinguished from lazulite, by the intenseness of its color.

A mineral of a fine azure-blue color, usually in small rounded masses. It is essentially a silicate of alumina, lime, and soda, with some sodium sulphide, is often marked by yellow spots or veins of sulphide of iron, and is much valued for ornamental work. Called also lapis lazuli, and Armenian stone.

A mineral of a light, indigo blue color, occurring in small masses, or crystallized in oblique four-sided prisms.

A mineral of a light indigo-blue color, occurring in small masses, or in monoclinic crystals; blue spar. It is a hydrous phosphate of alumina and magnesia.