Evening Republican, Volume 17, Number 284, Rensselaer, Jasper County, 28 November 1913 — Diamond Cleaving. [ARTICLE]

Diamond Cleaving.

The art of the lapidary is one of the most delicate employments of mechanical force known. The practical diamond cutter learns many tacts about precious stones which are Sealed books even to mineralogists. For instance, It Is the lapidaries Who have found out that diamonds owning from different districts vary remarkably In their degrees of huranees. It appears that the hardest diamonds known come from New Booth Wales. An unfamiliar fact Is that diamonds are made to assume approximately the required shape by slitting and cleaving and by "bruting,” which is the rubbing of one diamond against another, before they are submitted to the polishing wheel. In cleaving the diamond is cemented on the end of a wooden stick, and a steel blade is driven with a smart blow In the direction of the natural plane of cleavage. Diamonds that hare been cut by the lapidary’s wheel lack some of the brilliance possessed by those that have simply been steered. —New York Herald. The world’s coal mines yield 40fy> NUN tans of coal every year.