Baryte, barite or barytes is a mineral consisting of barium sulfate (BaSO4). It is generally white or colorless, and is the main source of the element barium. This group consists of baryte, celestine (strontium sulfate), anglesite (lead sulfate), and anhydrite (calcium sulfate). barite and celestine form a solid solution (Ba,Sr)SO4.
The radiating form, sometimes referred to as Bologna Stone, attained some notoriety among alchemists for the phosphorescent specimens found in the 17th century near Bologna by Vincenzo Casciarolo.
It is also a well-known gangue mineral in hydrothermal deposits on land and it is a principal component of moderate-temperature hydrothermal chimneys on mid-ocean ridges and volcanically active seamounts. Early work on the distribution of marine barite in deep-sea sediments.
Barium also has medical uses. Barium chloride use includes treating heart block, which is not in use due to the toxicity of barium chloride. Chemically pure barium sulfate is nontoxic to humans, due to insolubility, and is in use frequently as a contrast agent in the X-ray diagnosis of colorectal and upper gastrointestinal examinations. Barium-containing household and consumer products constitute a minuscule part of barium consumption.
The American Petroleum Institute specification API 13/ISO 13500, which governs baryte for drilling purposes, does not refer to any specific mineral, but rather a material that meets that specification. In practice, however, this is usually the mineral baryte.