bortz

See also: Bortz

English

Alternative forms

• boart, bort

Noun

bortz (uncountable)

1. Diamond of inferior quality, commonly used for drill tips; abrasive diamond powder; bort.
   • 1906 September, X-Rays and a Diamond Thief, Popular Mechanics, page 932,

     It is also noticeable that the black diamond, No. 20, a dull and lusterless substance, is as transparent to the X-rays as the brilliants, while the diamond bortz, No. 6, is much less transparent than either, though more so than the imitation, No 19.

   • 1939, Materials Engineering, volume 10, page 358:

     These main categories of industrial diamonds, gem stones, bortz, and carbonados, are further subdivided into smaller classes. For instance, particularly fine bortz of a round form composed of crystals radiating from a common center are known as ballas.

   • 1951, James Deans Cumming, Diamond Drill Handbook‎^[1], page 482:

     A large part of the production of the Belgian Congo is crushing bortz.