bismutin

Bismuthin is a rare mineral belonging to the sulfosalt group, characterized by its chemical composition of bismuth, antimony, and sulfur. The formula for bismuthin is typically represented as Bi₄Sb₂S₉, indicating its combination of these elements. This mineral is known for its metallic luster and dark gray to black color, often appearing in small, tabular or prismatic crystals. It is closely related to other sulfosalt minerals such as bismuthinite and aikinite, sharing similarities in structure and occurrence.

Bismuthin is primarily found in hydrothermal veins associated with other sulfide and sulfosalt minerals. It commonly occurs alongside minerals like bismuthinite (Bi₂S₃), stibnite (Sb₂S₃), and various sulfides of lead, copper, and silver. Notable deposits have been reported in regions such as the Czech Republic, Germany, and the United States, particularly in states like Colorado and New Mexico. Due to its rarity, bismuthin is not widely exploited for industrial purposes but is of interest to mineral collectors and researchers studying sulfosalt mineralogy.

The mineral was first described in the early 19th century, with its name derived from the Latin *bismuthum*, the historical name for bismuth, reflecting its primary constituent. Bismuthin’s formation typically occurs at lower temperatures compared to other sulfides, suggesting its presence in later-stage hydrothermal fluids. Its crystal structure is complex, featuring layered arrangements of bismuth and antimony atoms bonded to sulfur. While not economically significant, bismuthin serves as a valuable specimen for educational and scientific study, offering insights into the behavior of bismuth and antimony in mineral-forming environments.