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seals, brooches, penholders, etc. It exceeds rock crystal little if any in market price.
Sagenitic Quartz. This
form of quartz is variously known as " sage-nite," "fleche d'amour"
(love's arrow), "hair stone," "needle stone," , and if the included
mineral be rutile, "rutilated quartz." These terms all refer to
colorless crystallized quartz which is penetrated by hair-like crystals
of other minerals. An illustration of the occurrence is given in the
accompanying colored plate. Of the minerals so included rutile is the
most common, but tourmaline, hornblende, epidote, goethite, and others
occur. The inclusions have doubtless been formed in the quartz by
crystallizing at the same time with it, the quartz in this case being
the "host." The length of the included crystals may be considerable.
Some of the rutilated quartz from Madagascar has single included
crystals six inches long. The quantity of the included mineral may
vary from a few long, scattered individual crystals to a multitude of
short ones. For cut stones, pieces of the latter sort are usually
preferred. Some of the prettiest effects are produced when the included
mineral is rutile, and is sufficiently transparent to be of a blood-red
color by transmitted light. By cutting suitable pieces of this sort
into the form of hearts, the effect indicated by the term "love's
arrow" can be prettily obtained. Often the included crystals cross each
other nearly at right angles, thus giving the appearance of a network.
It is on account of this appearance that the name sagenite, from the
Greek sagene, a net, is given. Sagenitic quartz is obtained in
various localities. Madagascar is perhaps the chief source of supply at
the present time, much excellent material being obtained there. The
rock crystal of Brazil is frequently sagenitic also. Several localities
in the United States furnish sagenitic quartz, among them being North
Carolina, Rhode Island, and California. Perhaps the finest specimens
ever seen were gotten from some boulders found in the vicinity of
Hanover, New Hampshire, in the years 1830-1850. Crystals of quartz
containing hair-like crystals, or massive o:-scale-like inclusions of
chlorite, are obtained in Japan, which are prepared for ornamental
purposes simply by smoothing and polishing the natural crystal surfaces.
" Cat's-eye." " Tiger-eye." These
are forms of quartz containing fibrous inclusions, which, instead of
being scattered, are massed together, so that upon a polished surface a
sheen like that of silk is seen by reflected light. The term of
Occidental cat's-eye is often applied to cat's-eye of this sort, in
distinction from the Oriental cat's-eye composed of chrysoberyl. "
Tiger-eye" is made up of somewhat coarser fibers than cat's-eye. It is
of a golden yellow color, while the color of
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