more
used, or were more fond of Amulets. According to Oriental writers these
were frequently formed of Gold, Silver, and Precious Stones.
" There is little doubt" (Alchemy and Pharmacy) "
that the modern custom of wearing precious stones in rings, and as
charms for pendants to watch-chains, originated in the amulet, and the
talisman. Who can say that faith in such charms has yet altogether died
out ? The belief in keeping a crooked sixpence, or a broken ring, is
evidence of a peculiar vein of superstition which runs through most of
us, and which, strange though it may seem, the advance of science, and
education, has not altogether dispelled."
In
a Lecture on " Precious Stones," delivered recently before the Society
of Arts, Professor Miers explained the process by which crystallized
Gem-stones, true in many respects, can be produced by artificial means.
Diamonds,
for instance, of such a character, can be produced by dissolving
charcoal in molten iron, in an electric furnace, and cooling under
pressure : the resultant crystals being mere specks ; but they probably
represent the actual process by which true Diamonds have been generated
in meteorites.
By
similar means the Ruby has been successfully reproduced in Paris, on a
scale sufficiently large to be used in jewellry. The crystals thereof
are made by raising to a very high temperature a mixture of alumina,
potassium carbonate, and calcium fluoride ; the red colour being
obtained by adding a trace of potassium chromate. Then, by maintaming
the temperature for about a week, crystals weighing one-third of a
carat are obtained without any great difficulty. " These Stones,"
