Payargyrite - Dark Ruby Silver
Composition, Crystallization and Structure

Composition. Sulphantimonite of silver, Ag3SbS3 or 3Ag2S Sb2S3 = Sulfur 17.8, antimony 22.3, silver 59.8. sometimes contains a small amount of arsenic. Compare propustite.

Crystallization. Hexagonal-rhombohedral; hemimorphy.

Crystals prismatic with rhombohedral and scalenohedral terminations. Usually distorted and often with complex development. Frequently twinned.

Structure. In crystals or massive; compact; in disseminated grains.

Physical Properties. Rhombohedral cleavage. H. = 2.5. G. = 5.85. Luster adamantine. Color usually dark red to black, in thin splinters deep ruby- red. Indian-red. Strack.

Tests. Fusible at 1. on charcoal gives dense white coating becomes tinged with a reddish color near assay sue to a small amount of Volatilized silver. Odor of sulfur dioxide and contains of antimony oxides when heated in O. T. Decomposed by nitric acid and solution with hydrochloric acid gives white precipitate of silver chloride. Characterized chiefly by its dark red color and streak.

Occurrence. A rare silver minerals associated with proustite, argentite, galena, calcite, etc. primary in origin and commonly found in the upper portion of silver veins. Found in the silver mines at Andreasberg, Harrz Mountain; at Freiberg, axony; Pribram, Bohemia; in Guanajuato, Mexico; at Chañarcillo, Chile; in Bolivia. Found in various silver veins in Colorado, Nevada, New Mexico, Idaho, etc.

Name. derived from two Greek words meaning fire-silver.

Use. An ore of silver.