Baryte, or barite, (BaSO4) is a mineral consisting of barium sulfate). The baryte group consists of baryte, celestite, anglesite and anhydrite. Baryte itself is generally white or colorless, and is the main source of barium. Baryte and celestite form a solid solution (Ba,Sr)SO4 together.
The radiating form, sometimes referred to as Bologna Stone, attained some notoriety among alchemists for the phosphorescent specimens found in the 1600s near Bologna by Vincenzo Cascariolo.