SEMI-PRECIOUS STONES OCCASIONALLY USED
T
HE mineral world
contains many beautiful materials that are without the pale which
encloses the clearly defined gem stones; these " outlanders" may be
classed as semi-precious stones that are only occasionally used, and
while many are truly beautiful and others are interesting, because of
rarity or peculiarities, all lack some quality—usually a sufficient
degree of hardness—which would admit them into the patrician rank of
Precious Stones. Because of their intense scientific interest,
technical mineralogists, who have written books about gems, not only
include but devote considerable space to minerals that will not meet
the eye of one manufacturing jeweller or gem dealer in one hundred, or
ever be seen by one gem buyer in thousands. These stones are usually
not so rare in nature as they are in stores, and their cutting and
mounting is usually the result of
an individual order; otherwise they are col-
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