America, the name of Vesuviana was changed to that of idocrasium, which is derived from eî8dos, form, and κράαsις, mixture, which is intended to signify the multitude of forms under which it is naturally found.
When transparent, and of a pure green or brown, it is used for rings and pins, and is principally worked in Naples and Turin.
It is cut on a leaden wheel, and receives polishing by means of the pumice-stone.
It is of little value, and is very little known to foreign traders.
The Neapolitan idocrasium is often called in mineralogy the Italian chrysolite ; it
is, however, different from the true chrysolite, having much less
specific gravity. It was even mistaken for green garnet, but the
hardness of the latter is much greater.