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bowing outward ; but when mechanically trimmed to perfect their shape, each line and angle must be unerringly true.
Fig. 4 is a cube of six faces having its corners rounded or flattened, and Fig. 5 is a double cube or dodecahedron, having
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twelve equal rhombic faces. Some diamonds can
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readily
be made to receive these shapes with little loss of substance. Fig. 8
represents a gem shaped as a parallelogram with a facet on one upper
corner, the lower side showing
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It is called " Indian " or " Lustre of India."
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Figs. 6 and 7 represent the oldest and simplest form of gem cutting, called the " table cut." It suits the other precious gems
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much better than the pure diamond. A celebrated " table " diamond was given by Prince George (afterwards George IV.)
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to Mrs. Fitzherbert. She had it split along the line from a to b, and used each half to fit in the face of a locket; one
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holding
her own portrait, and the other that of her princely lover. The diamond
with the portrait of Mrs. Fitzherbert was buried with the old king in
the locket which hung on his neck.1
The first and simplest modification of
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the
"table cut" of a diamond is called the "Old English single" or the
"star single cut." By this arrangement the table cut diamond had its
top part planed down about the edges to represent an eight-pointed star
whose centre figure was an octagon, or elongated octagon, if the stone
was longer than its width. This style of cutting appears in sets of old
diamonds for crown jewels or ordinary wear. These sloping triangular
faces were ground upon the edge of the upper surface of the stone only,
reaching from the flat part, which is then technically called the "
table," to the central line which is called the " girdle," and these
cut surfaces are called " facets" or small
1 " Macaulay's Essays," Thomas Babington Macaulay.
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