we
now understand a mineral which by its hardness, rarity, lustre or
colour is used for the purposes of adornment; a precious stone is also
usually a mineral, and possesses these same qualities in a minor
degree. Most of the true gem stones are crystallised and are
transparent or at least translucent. Formerly, however, besides
including all the then known stones that fell under the above heads,
many substances were regarded as precious stones which were of a very
different origin, and that often for very different reasons than on
account of their beauty. Fossils, for instance, were at one time held
in high esteem in this relation and were accredited with great use in
the preparation of medicinal remedies, and that apparently chiefly on
account of their peculiar shapes. Again, we find that when glass was
scarce a cup of that material was considered fit to rank with ornaments
made from what we still regard as precious stones.
The
individual properties ascribed to the various stones will be noticed in
the part dealing with each substance, but a few general examples may be
given here to illustrate the point. The Diamond, for instance (though
not known to the earliest writers), is frequently referred to on
account of some of the following reputed properties : taken internally
it is a violent poison—it is said to have been administered to Sir T.
Overbury (amongst other poisons) when a prisoner in the Tower—and yet
Garcias records a case that came under his notice of a woman giving her
husband repeated doses of diamond-dust to relieve dysentery, but
without effect; the physician Camillo Leonardo in the sixteenth century
declares it is a poison of a most violent kind, and Cellini tells how
an enemy tried to poison him by employing
