chlorargyrite

Chlorargyrite is a mineral species with the chemical formula AgCl. It is a halide mineral of the argentian group and crystallizes in the isometric system, typically forming tabular or pseudo-cubic crystals, though it is more often found as granular masses or crusts. Fresh surfaces are usually white to gray, and the mineral has a vitreous luster with a white streak. Its hardness is about 2.5 on the Mohs scale, and it has a relatively high specific gravity of around 5.5.

Chlorargyrite forms as a secondary mineral in the oxidized zones of silver-bearing hydrothermal deposits or through chlorine-rich fluids interacting with silver minerals. It commonly occurs in veins and fracture cavities and is frequently associated with native silver, argentite (silver sulfide), cerargyrite, and other chloride minerals. In some literature, chlorargyrite is discussed alongside older names such as cerargyrite or horn silver, reflecting historical usage for silver chloride minerals.

Etymology and significance: the name derives from its chlorine content and its argentiferous composition. Although not a major ore in modern mining compared with other silver minerals, chlorargyrite has historical importance as a source of silver and is collected for its mineralogical and chemical properties. It occurs in silver-rich districts worldwide and is of interest to mineralogists and collectors for its distinct chemistry and isometric crystal habit.