stones
would be unlimited; but this, as we shall see, is far from being the
case. We must remark, however, that it is impossible to draw a hard and
fast line between the most common predates stones and ordinary stones, since we have here a particular case of the grand law formulated more than a century ago by the illustrious Linnaeus: Natura non facit saltus—" Nature never makes a leap."
ORIGIN OF PRECIOUS STONES.
All
precious stones are transparent, or at least translucent, from which it
may be concluded that the matter of which each consists is homogeneous.
Now this homogeneity could never have been attained by the mixture of
their elements in the solid state, however finely these may have been
pulverized, and hence they must have been in the condition of either
gases or liquids. Nature has a multitude of means by which these
transformations of matter are effected, all referable to three general
processes:—
1st. Direct fusion of the substance by the action solely of heat.
2d. Dissolution of the substance by the aid of foreign substances at variable temperatures.
3d. Bringing together, in the state of vapours, substances destined to become the elements of the stone.
