ing no magnetic action whatever,
we have a long, graduated scale, in which many of the precious stones
appear, those containing iron in their composition being more or less
responsive, as already mentioned, and that either in their normal state,
or when heated, and always to an extent depending on the quantity or
percentage of iron they contain.

In this case, also, science has not as yet been able to introduce into
an artificial stone the requisite quantity of iron to bring it the same
analytically as the gem it is supposed to represent, without completely
spoiling the colour. So that the behaviour of a stone in the presence of
a magnet, to the degree to which it should or should not respond, is one
of the important tests of a genuine stone.

CHAPTER XI.

THE CUTTING OF PRECIOUS STONES.

As existing in a state of nature precious stones do not, as a rule,
exhibit any of those beautiful and wonderful properties which cause them
to be so admired and sought after as to become of great intrinsic value,
for their surfaces have become clouded by innumerable fine cuts or
abrasions, because of the thousands of years during which they have been
under pressure, or tumbled about in rivers, or subjected to the
incessant friction caused by surrounding substances. All this occurring
above and under ground has given them an appearance altogether different
to that which follows cutting and polishing. Further, the shape of the
stone becomes altered by the same means, and just as Michael Angelo's
figure was already in the marble, as he facetiously said, and all he had
to do was to chip off what he did not require till he came to it, so is
the same process of cutting and polishing necessary to give to the
precious stones their full value, and it is the manner in which these
delicate and difficult operations are performed that is now under
consideration. Just as experience and skill are essential to the
obtaining of a perfect figure from the block of marble, so must the
cutting and polishing of a precious stone call for the greatest
dexterity of which a workman is capable, experience and skill so great
as to be found only in the expert, for in stones of great value even a
slight mistake in the shaping and cutting would probably not only be
wasteful of the precious material, but would utterly spoil its beauty,
causing incalculable loss, and destroying altogether the refrangibility,
lustre and colour of the stone, thus rendering