Diamond Culling

Information on Diamond Culling.

Diamond Culling

By the operation of cutting, the natural crust of the diamond is removed, and the stone is formed into the shape required.  In order to cut a diamond, two stones are employed, which are fastened into two sticks, the tops being filled with cement, into which each dia mond is inserted, leaving exposed the part to be cut.

The workman, who has leathern gloves on his hands, as well as a leathern stall on the right thumb, takes a stick in each hand, and leaning them against two up right pieces of iron, fastened on the edge of the cutting-bench, rubs the two diamonds together until he has produced a flat even surface (which is a facet),  instead of the concave or convex form of the natural stone.  The dust or diamond powder which falls is re ceived in a square box, containing oil, and the powder is burnt before being used, to free it from the particles of cement that become mixed with it.  By this means two facets are cut on two different stones at the same time.

During the cutting, the workman examines the facets by means of moistening the stone with the tongue, first taking care to remove any powder with a camel's hair pencil.  When the facet is formed, the cement is heated, and the diamond taken out, and replaced so as to expose a different surface until the cutting is completed.  It must be understood that by this opera tion only the general outline of the form is made.  A stone which would have when quite completed fifty eight facets, including the table and culet, receives in cutting only eighteen, eight of which are the surfaces of an octahedron or double pyramid, and are formed by the taking away eight edges or angles of these eight surfaces, one for the whole table, and one for the cut.

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