BORT CARBONS, ETC. 331
refraction,
and dispersion. Though one familiar with diamonds cannot be deceived on
inspection, under some conditions when worn, a fine paste will escape
detection. The surface brilliancy is often very beautiful. Though it
will not entirely hide the internal weakness and vacancy of glass when
at rest, it is confusing when in motion. In order to hold the light
entering the stone from passing out at the back, which gives a glass
diamond its weak, lack-luster appearance when at rest, the back is
sometimes entirely covered with foil. These are used for close-set
jewels, in which the backs of the stones are not seen. For openwork
setting, the foil is put on and just around the culet. But these are
not popular except in cheap gold jewelry, as the foil at once betrays
the imitation even to the inexperienced, and most of those who wear
paste jewels are at least willing that the observer shall have a chance
to believe them real gems.
Paste
diamonds are not as ancient as imitation colored stones. The Egyptians,
Phoenicians and Romans were adepts at manufacturing spurious emeralds,
rubies, and similar stones, but they did not imitate the diamond.
Perhaps no better evidence exists of the late recognition of the
diamond as a jewel than the fact that it was not imitated prior to the
seventeenth century. Since then paste has glittered on the persons of
thousands who loved, but could not afford diamonds, and has shone from
the buckles and belts of many who though rich, thought them good enough
for certain purposes. Years ago the jewels of the stage were well-nigh
all glass, but now popular singers and actresses wear gems both rich
and rare.
