continents;
mountains of ice, of which the Alpine glaciers are but meagre vestiges,
invaded even the most temperate zones; streams of irresistible violence
—such as the great rivers of our day can scarcely give us any idea
of—furrowed the earth. Under the influence of these agencies, the
stupendous forces of which were all working in one direction, the
grinding down and destruction of the rocks was effected over vast
spaces, and to considerable depths. Now it is precisely in the debris
of igneous rocks, whose reduction to sand was accomplished during this
period, that the greater number of precious stones are found; and above
all, the diamond.
But
although the diamond-producing soils are comparatively modern alluvial
formations, it must not be concluded that the diamond, and the other
precious stones which accompany it, are of recent origin. In reality,
that which is recent is the reduction of the rocks to the alluvial
state; but the rocks themselves, and consequently the precious stones
that they contain, are often extremely ancient. There are precious
stones whose existence was anterior to the first sedimentary
formations; they had their place in the world long before the plants
and animals began their measureless succession; and they are an
inheritance to man from the azoic age, when as yet no foreshadowing of
his existence had fallen upon the globe.
