bort

Bort is a term in the diamond industry used to describe diamond material that is not suitable for gemstone use. It usually refers to rough, unpolished stones that show unfavorable color, clarity, or structural flaws, making them unsuitable for faceting into gems.

Bort includes natural diamond fragments that do not meet gem-quality standards and, in many cases, is processed into abrasive powders or used as industrial diamond components such as grinding wheels and drill bits. The term emphasizes utility for non-jewelry applications rather than aesthetic value.

The term is sometimes used interchangeably with boart, though some sources distinguish boart as rough pieces or fragments from mining debris; usage varies regionally and historically.

Value and market: Bort generally has little or no gem value and is priced accordingly as industrial-grade material. It remains an important source of diamond for industrial applications because of the material’s hardness and wear resistance.

See also: industrial diamond, rough diamond, diamond.