ENGRAVED AND CARVED GEMS 131
ander on the obverse, while the reverse bears the Greek monogram of the name Christos.
After
the third or fourth century of our era the art of gem-engraving seems
to have been lost, or at least to have been very seldom practised, and
it is noteworthy in the matter that after this period writers who treat
of the virtues of engraved gems as talismans rarely, if ever, use the
words "if you engrave" such or such a figure on a stone, but write "if
you find" such a figure.
The
figures engraved on precious stones were supposed to have a greater or
lesser degree of efficacy in themselves independent of the virtues
peculiar to the stone on which they were engraved, and this efficacy
depended largely upon the hour, day, or month during which the work
was executed. For the influence of the planet, star, or constellation
which was in the ascendant was thought to infuse a subtle essence into
the stone while the appropriate image was being engraved. However, to
exert the maximum power, the virtue of the image must be of the same
character as the virtue inherent in the material, and the gem became
less potent when this was not the case. Certain images, those
symbolizing the zodiacal signs for instance, were looked upon as
possessing such power that their peculiar nature impressed itself
even upon stones inherently of different quality; others again were
only efficacious when engraved on stones the quality of which Was in
sympathy with them.21
Naturally,
many of the ancient gems which had been preserved from Greek and Roman
times were recognized as being purely products of art, but in medieval
and later times the idea of the magic quality of all engraved gems had
become so deeply rooted that in many cases a magical
31 Camilli Leonardi, Speculum Lapidum, Venetia, 1502.
