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844
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MINERAL RESOURCES.
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In
the Hatch mine, near the top of Mount Apatite, feldspar is the
principal product. Some tourmaline was obtained from the first opening
made in 1882.
The
Berry mine, about 2 miles south of Mount Apatite, is chiefly a feldspar
deposit. Pink and green tourmaline of gem quality are occasionally
found.
The
Merrill mine is in the township of Hebron, about 16 miles northwest of
Mount Apatite. The "vein" is 12 to 14 feet wide, and lies in mica
schist. Only a small amount of work has been done here, though some
very deep-colored red tourmalines were obtained.
COLORADO.
C.
A. Beghtol, formerly of Canon City, mined for tourmalines at two places
north of the Royal Gorge of the Arkansas during 1906 and 1907. These
were the Royal Gorge No. 1 mine, 5 miles N. 70° W. of Canon City, and
the Royal Gorge No. 2 mine, 4 miles due northwest of Canon City. The
No. 1 mine is in the east wall of a canyon entering the Royal Gorge
from the north and about 200 yards from the gorge and about 300 feet
above the bottom of the canyon. The country rock is muscovite-biotite
gneiss, cut by numerous pegmatites ranging from an inch to several feet
in thickness. The pegmatites are approximately conformable with the
gneiss, which strikes about northeast with a nearly vertical dip. The
tourmalines were found in a vein along the northwest side of a 4-foot
pegmatite. The pegmatite has resisted erosion better than the
inclosing gneiss and stands out as a high wall on the steep side of the
canyon. The vein was found through a distance of only 6 feet, and then
pinched out. It is reported to have been a lens-shaped pocket nearly a
foot thick in the thickest part and to have yielded some very fine
pink, green, and colorless tourmaline crystals. No further work was
done after the gem pocket had pinched out. A quartz streak along the
wall of the pegmatite contained much well-crystallized black
tourmaline and small mica crystals.
The
No. 2 mine is on the dissected plateau north of the Royal Gorge and
about 2 miles from the gorge. It is in a low oval hill about 200 yards
east of the Mica Hill mica mine. Each of these hills is composed of
pegmatite inclosed in contorted biotite and hornblende gneiss. The two
outcrops of pegmatite do not appear to be connected, and have yielded
unlike minerals. In the mica mine both beryl, in crystals up to 6
inches in diameter, and columbite, in masses of several pounds weight,
have been found. The pegmatite of the No. 2 mine contains colored
tourmaline and lepidoliteor lithia mica. The lepido-lite has been found
in streaks and irregular masses up to several inches in thickness in a
number of places in the pegmatite. Much of the tourmaline is associated
with the lepidolite, though some is inclosed in feldspar and quartz. At
the time of the writer's visit no pockets or cavities with tourmaline
crystals were exposed, and the tourmaline observed was "frozen" in the
pegmatite. The colors observed in different crystals and in different
parts of the same crystals were light and dark lilac pink, light and
green, and very dark indigo color (blue). Part of the tourmaline is
partly decomposed or altered to a softer mineral, though still
retaining the form and colors of the tourmaline. The greater part is
opaque to translucent, though some transparent gem material is reported
to have been found.
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