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64
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PRECIOUS STONES
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reflections
of the table-cut stones. It is the opinion of the writer that the
centre facets are helpful to shallow stones, and serve to hide defects
and color by distracting the vision and confusing the eye in its
efforts to locate flaws and measure the quantity of color. In effect
this cut is an improvement on the double rose, Fig. 8, Plate XIII., or
cutting such as shown in the " Florentine" brilliant, Fig. 3, Plate
XVIII.
The
diamond, being the hardest of all known bodies, can be cut only by
means of powdered diamond. This powder is prepared from bort, which is
diamond too faulty for use as jewels, or the refuse of cleaving and
cutting. These pieces are pounded in a mortar of hardened steel, and
the powder is used to charge the wheels upon which the diamonds are
ground.
The
first process is to examine the crystal and decide which way it shall
be cut to get the best results. Flaws and imperfections in the
finished stone must be avoided as far as possible, proportion
preserved, and none of the precious material wasted which is not
absolutely necessary in order to secure the most value in the finished
product. The cutter having decided, he takes two diamonds, and,
affixing them on the ends of two box-wood sticks made for the purpose,
begins the actual work of cutting by " bruting," or rubbing them
against each other. Having prepared it to his satisfaction, the stone
is given to the setter, who sets it in a mixture of lead and tin melted
in a metal cup resembling somewhat an old-fashioned egg-cup. A small
part of the diamond is left exposed, a mark indicating the grain of the
stone is made upon the solder, and, when it is set, it is handed to the
polisher, who proceeds to grind it upon the mill first to produce the
" table." This done, it is reset for the first or flat corner, and so
on successively until all the facets are cut. During the entire process
the direction of the grain is noted, and a mark indicating it is made
on the solder by the setter for the guidance of the polisher. Each
facet has a name, by
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