localities,
but the mineral in its rarer form of emerald is comparatively of very
rare occurÂrence. The emerald or green beryl, as it should be
scientifically known, has long been the most highly prized of the green
gems. In brilliancy it exceeds all other green gems excepting only the
very rare green sapphire. The most valuable specimens exhibit a vivid grass-green shade,
and it is to this color that they owe their great value. Other
considerations, such as freedom from imperfections, are quite secondary
in determining the value of the stone. In fact a perfect emerald is
almost never found, and this circumstance has passed into an Eastern
simile which runs, "As scarce as a perfect emerald," this being a
symbol for the acme of rarity. The emerald is light in weight and an
emerald of a given size will be about a third larger than a diamond and
forty-five per cent larger than a sapphire of equal weight. The
distinctive color of the emerald is probably due to a trace of chromium in its composition.
The
largest source of supply of fine emeralds is a mine in Muso, a locality
about seventy-five miles northwest of Bogota, in the United States of
Colombia. This mine has been worked almost continuously since 1558, but
the wildness of the region and the barbarity of the aborigines
