Barite Composition,
Crystallization & Structure

Barite - Barytes, Hesvy Spar
Composition. Barium sulphate, BaSO4 = Sulfur trioxide 34.3, baryta 65.7. strontium and calcium sulphastes present at times.

Crystallization. Orthorhombic. Crystals usual tabular parallel to base; often diamond shaped because of the presence of a short prism (Fig. 351). Both macro-and brachydomes usually present, either beveling the corners of the diamond-shaped crystals (Figs. 352 and 353), or, if the prism faces are wanting, beveling the edges of the tables and forming rectangular prismatic-shaped crystals elongated parallel to either the brachy- or macro-axis (Fig. 354 and 355). Crystals sometimes quitecomplex.

Structure. In crystals. In divergent groups of tabulas crystals forming “crested barite.” Also coarsely laminated; granular, earthy.

Physical properties. Perfect cleavage parallel to base and prism faces. H. = 3-3.5. G. = 4.5 (heavy for a nonmetallic mineral). Vitrous luster; pearly at times on base. Colorless, white, and light shades of blue, yellow, red. Transparent to opaque.

Test. Fusible at 4, giving yellowish green barium flame. After ignition gives an alkaline reaction on moistened test paper. Fused with sodium carbonate and charcoal dust gives a residue, which, when moistened, produces a dark stain of silver sulfide on a clean silver surface. Recognized by its white color, high specific gravity, characteristic cleavage and crystals .

Occurrence. Barite is a common mineral of wide distribution. It occurs usually as a grangue mineral in metallic veins, associated especially with ores of silver, lead, copper, cobalt, manganese and antimony. Sometimes in veins in limestone with calcite and celestite or n sandstone with copper ores. At times acts as a cement in sandstone. Deposited occasionally as a sinter by waters from hot strings. Notable localities for the occurrence of crystaline barite are in Westmoreland, Cornwall, Cumberland, and Derbyshire, England, Felsobanya and other localities, Rumania; in Saxone and Bohemia. In the United States at Cheshire, Cocnecticut; Dekalb, New York; fort Wallace, New Mexico. Massive barite, occurring usually as veins, nests and irregular bodies in limestones, has been quarried in the United States in Georgia, Tennessee, Missouri, etc.

Use. Barite is used chiefly for the production of barium hydroxide, employed in the refining of sugar. It is ground and used as a white pigment; to give weight to cloth and paper, etc.