Page:A treatise on diamonds and precious stones including their history Natural and commercial.djvu/174

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138
CUTTING AND POLISHING

end of the stick: thus the angle the facet makes with the girdle is greater or less, as the stick is inserted in a higher or lower notch. The peg not only tends to keep the hand steady, but is the cause of the facets being cut true, and always forming the same angle. In step cutting, it is particularly useful; otherwise it would be difficult to place the rows of steps parallel to each other.

To assist the lapidary, quadrants, angles, &e. have been formed with mathematical exactness, in which the stone is placed to be cut and polished; but our workmen have rejected their use, considering them only fit for novices, and depend wholly on tact and a well-practised eye.

The slitting of precious stones, which is a very important branch of the lapidary's busi-