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22 HISTORY OF THE GEMS FOUND IN NORTH CAROLINA.
resemble
in form those from Yogo Gulch, Montana (the sapphire variety) which are
taken from true igneous dikes; and these flat and tabular hexagonal
forms are regarded by students of crystallography as characteristic of
corundum that has solidified from a molten igneous rock.
Another
corundum occurrence in saprolitic rock, but the crystals blue and more
prismatic, is noted by Dr. Pratt at the Reed, or Watauga mine, 6 miles
east of Franklin; and red, sometimes ruby, corundum is found in old
stream gravels near West Mills; both of these are in Macon County. A
number of minor occurrences are known throughout the general region,
where there are small saprolitic areas.
There
are many other localities of corundum in this group of counties, some
of the more important or promising of which may be simply mentioned
here. In Macon County, besides the important occurrences already
described, corundum appears at Glenville, in chlorite schist; at Xona,
on Thumping Creek, in nodules and flat crystals in gneiss; on Hickory
Knoll Creek at an elevation of 4,000 feet on Fishhawk Mountain, in
dunite; and at the Coweeta mine, of pink color in greenish cyanite. Of
late, the emery variety has been found, and to some extent worked, at
several points near Fairview Knob, in a basic magnesian rock, the
principal mine being the Fairview, near North Skeener Gap, and the
Waldroop mine on Dobson Mountain.
Jackson
and Transylvania counties have numerous corundum localities, notably in
the region along their border, where the town of Sapphire has been
named, and the appellation of the Sapphire country is frequently used.
Here are found many outcrops of peridotite, with a general X.E.-S.W.
course, and frequently associated with corundum. One locality that
gives some promise is the so-called gem mine on the property of Dr.
Grimshawe, of Montvale. This has been known and to some extent worked,
for many years. Rubies of good color, from which a number of fine but
very small stones have been cut, have been found here in the gravels of
the stream, together with blue and yellow corundum of gem quality. By
following up the gravels the corundum was located in a small vein in
the decomposed peridotite.
At
the Sapphire and Whitewater mines, near Sapphire, fragments of corundum
of a fine blue color have been found, from which small but good gems
have been cut.
Quite
large amounts of commercial corundum have been taken out at the Bad
Creek and Socrates mines, and also at the Burnt Rock and Brockton
mines; these two are in Transylvania County, the others being in
Jackson County, and all in peridotite. Other associations in Jackson
County are, along Caney Fork and Chastain's Creek, in chlorite schist;
and at Bett's Gap in translucent grayish-white crystals in gneiss.
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