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Where Precious Stones are Found.
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favourable to the blossoms of the inorganic world, than the dark skies of the north.
But
although modern researches have shewn that Precious Stones are not
limited to any defined geographical area, their distribution is yet in
a measure circumscribed, inasmuch as they are not met with in all
mountain ranges, nor in all geological formations. The most valuable
are found in such ranges as are composed of rocks considered to be
among the most ancient in the world—in rocks composed of granite,
gneiss, porphyry, mica-schist, and crystalline limestone. Sometimes
they occur imbedded in the mass of the rock ; at other times,
protruding, as it were, from the surface and jutting forth into free
cavities, When they are thus found in the very rocks where they were
originally formed they are said to be in their primitive bed.
Many however, are found far from their primal home, in a derivative or secondary deposit, in diluvial or alluvial soils, in the
gravels or sands of river-beds. This last mode of occurrence is perhaps
the most frequent for the finer Precious Stones. Far removed from their
native home by the force of heavy rains and rushing torrents, they have
been loosened and carried onwards, rounded by friction against the débris with
which they have been accompanied in their course. It is a strange fact
that those stones which have been washed in the currents or deposited
in river-beds, are generally found to be the finest. Possibly this may
be explained by a process of natural selection which has weeded out the
faulty stones, and left only those that, by their superior hardness,
could survive the rough usage to which they have been subjected. It is
their hardness and density that have not only preserved them from
destruction, but have enabled many to retain traces of their original
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