A fine fibrous variety of either calcite or gypsum, with a pearly luster.

A crystallized variety of dolomite, having a pearly lustre.

A weapon consisting of a bomb placed at the end of a long pole, or spar, and attached to a boat. The weapon is used by running the end of the spar into the enemy ship.

(mineralogy, informal) potassic feldspar

plural of spar-hawk

Synonym of cryolite

A variety of feldspar remarkable for its transparent ice-like crystals.

(mineralogy) native barium sulphate; barite.

plural of spar deck

(nautical) The upper deck of a ship.