Page:A treatise on diamonds and precious stones including their history Natural and commercial.djvu/108

 mond in that part where the facet is to be placed. This being done, the cement is softened by heat, and the position of the diamond is changed, in order to bring a fresh part under the operation of cutting. When all the facets have been placed upon the surface of the diamond, the cutting is completed. The stone, if examined, now presents rough edges and dull surfaces, resembling a piece of unpolished glass: these imperfections are removed by polishing, which gives the greatest sharpness to the angles.

shape of many Diamonds is so irreguJar, that it is necessary to remove pieces of considerable magnitude, in order to bring them to a form proper for cutting. Where the lines of these proposed sections coincide with the lamellar structure of the stone, the workman has recourse to the delicate and perhaps somewhat hazardous operation of splitting, by which a double advantage is obtained. In the