GEMS AND PRECIOUS STONES. 657
the
pit, incloses numerous beryl crystals. These crystals are exposed in
the bare rock associated with feldspar, opaque and translucent quartz,
and a little mica. They range up to 2-1/2 inches in diameter, and one crystal measured about 1-1/2 inches by 10 inches. The pegmatite is exposed for thicknesses of 6 to 12 feet along its outcrop and was followed about 200 feet
farther northeast. In places along this outcrop nodules or small masses
of translucent quartz are exposed. The pegmatite is in contact with
coarse granite above, but the country rock is chiefly mica gneiss
intruded by granite and pegmatite in masses of various sizes. About
one-third of a mile farther northeast a large pegmatite forms the floor
of a bench on the hillside and outcrops as a wall around its lower
side. Several prospects have been opened within a distance of 200 feet
east and west in the floor of the bench and in these, greenish,
yellowish-green, and pale-golden beryl has been found. Most of the
crystals are opaque, but some contam translucent and clear portions
suitable for gems. The pegmatite is composed of coarse potash feldspar
crystals, massive quartz, in part translucent, and muscovite mica. In
the wall of the pegmatite below the bench there was an impression in
the pegmatite from which ahexagonal crystal, evidently beryl, 3 by 12
inches had been removed. This crystal was larger than those found in
the prospects on the bench. Durgin Mountain is 4 miles N. 30° W. of
North Lovell. The prospect visited is on the east side of the mountain
on the land of Ernest Bartlett, of East Stoneham. A small prospect had
been blasted out of an outcrop of hard pegmatite on the slope of the
hill. The pegmatite above the pit is covered with soil and grass.
Potash feldspar crystals, 1 to 2 feet thick, are exposed in the pit
along with large quartz segregations, some of which are beautifully
translucent. Muscovite and oiotite mica are both present. Beryl is
abundant in crystals ranging up to more than 2 inches thick.
They are mostly opaque or only translucent, but some fragments of
crystals were seen on the dump having small brilliant transparent
portions that were dark golden yellow, yellowish green, bluish green,
and nearly colorless. Most of the beryl crystals seen were exposed for
a distance of 15 feet in a streak or belt extending north across the
pegmatite outcrop. The beryl locality on Chapman Hill is about 3 miles
due north of North Lovell. Two prospects have been opened on the summit
of the hill near the east side, one in a field and the other one-fourth
mile south in the woods. At both places the openings are small, not
over 8 feet deep. The country rock at each place is biotite granite
gneiss, but the relations between it and the pegmatite were not
exposed. At both prospects rough crystals of orthoclase or microcline,
coarse quartz segregations, and crystals of mica, black tourmaline,
cleve-landite, and beryl were observed. Small pieces of blue and
bluish-green beryl of good color were found on the dumps, and these
prospects are reported to have yielded blue beryl of fine color.
Fine
golden beryl and aquamarine are reported to have been found on the land
of Charles Andrews, on Speckled Mountain, in the town of Stoneham,
about 5 miles northwest of North Lovell.
George
F. Kunz * described two fine beryls picked up in pastures in Stoneham
in 1881. One of these was cut into a bluish green brilliant gem
weighing 133J carats of nearly perfect quality and into
1 Gems and precious stones of North America, pp. 92-93,
