Argentite: Discovering the Allure of Argent A Rare and Stunning Silver Mineral Argentite is a silver sulfide mineral with the chemical formula Ag2S. It forms in low temperature hydrothermal vein deposits where silver and sulfur bearing solutions interact with host rock minerals. Argent crystallizes in the isometric system and is commonly found as cube-shaped or octahedral crystals. Its color ranges from dark gray to bluish-gray or black depending on impurities and crystal...