3-531: Ballas (or shot bort ) is a diamond industry term for roughly spherical shards of non- gem -grade diamond, mostly mined in Brazil and South Africa . A ballas is an aggregate of diamond grains concentrically arranged with radiating structure into a roughly spherical stone with a fibrous texture and without throughgoing cleavage planes. Tougher and more difficult to cleave than crystalline stones, ballas are used as industrial diamonds . This article about
6-429: A specific mineral or mineraloid is a stub . You can help Misplaced Pages by expanding it . Bort Bort , boart , or boort is an umbrella term used in the diamond industry to refer to shards of non- gem -grade/quality diamonds. In the manufacturing and heavy industries, "bort" is used to describe dark, imperfectly formed or crystallized diamonds of varying levels of opacity. The lowest grade, "crushing bort",
9-804: Is crushed by steel mortars and used to make industrial-grade abrasive grits. Small bort crystals are used in drill bits . The Democratic Republic of the Congo provides 75% of the world supply of crushing bort. Bort is commonly used as an abrasive . Smaller flakes and particles are used as an additive for scouring or polishing pastes and agents. Larger particles can be added to cutting, drilling and grinding tools to improve their lifespan and substantially increase their efficiency. Bort particles varying from one to two nanometers are added to lubricants such as paraffin oil . These particles will embed themselves into minute irregularities and imperfections of moving-part surfaces. Particles that remain suspended in
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