Quartz
also occurs in smaller masses scattered through the pegmatites. Some of
this quartz is highly translucent to almost clear, and some is smoky.
Mica occurs in yellowish-green crystals 2 to 3 inches across. Beryl is
abundant in crystals ranging from less than an inch to 15 inches in
diameter. They occur mostly along the quartz veins, some of the larger
ones displacing the quartz. The beryls exposed at the surface are
mostly opaque, but some contain translucent portions. They range from
nearly white to yellowish, to bluish green and to greenish blue in
color.
NEW HAMPSHIRE.
Beryl
crystals, some suitable for gems, have been found at several places in
the town of Roxbury, a few miles east of Keene, N. H. A number of these
have been cut by Leon Allen, a lapidary of Keene, with very good
results. Among localities where the crystals occur are Bassett Hill, 5
miles north of east of Keene; Horse Hill, 4\ miles east of
Keene; and the Keene granite quarry, on a hill 3 miles south of east of
Keene. Still other locahties nave been found but were not visited. At
all of the prospects the beryls have been found in pegmatite.
The
surface of Bassett Hill is rolling and stands 200 to 300 feet above the
surrounding country or over 1,600 feet above sea level. It is covered
with overgrown fields and small pine thickets on the summit and east
side and with woods on the west side. The country rock is granite
gneiss over most of the hill. Beryl crystals have been found in two
ledges of pegmatite on the east side of the hill and in one on the west
side. On the east side the outcrop of the lower ledge is exposed for a
distance of over 100 yards in a north and south direction. At three
places beryl crystals have been found in small openings blasted or cut
into the pegmatite outcrop. The vein is about 10 feet thick. It
contains smoky and translucent gray quartz, gray orthoclase crystals,
plates of greenish muscovite, and beryl crystals. One beryl crystal
found at the time of visit was opaque and gray on the outside and pale
yellow with clear portions between fractures in the interior. The upper
pegmatite ledge on the east side of the hill outcrops with a strike of
N. 10° E. and a dip of about 20° W. It is several feet thick, with a
zone of coarse-grained rock 2 feet thick next to the hanging wall.
There are a few small pockets 1 to 3 inches in diameter at the base of
this rock. Among minerals observed in the pegmatite are gray orthoclase
crystals, quartz in small masses and graphically intergrown with
feldspar and mica, black tourmaline crystals, some arranged in
rosettes, and colorless but more or less fractured beryl crystals up to
2 inches in diameter.
Pale-colored
beryl crystals have been found in the pegmatite outcrop on the west
side of the hill. The pegmatite at this prospect is coarse-grained,
containing orthoclase crystals up to 10 inches thick, segregations of
quartz over a foot thick, and crude mica crystals 2 to 3 inches across.
Most
of the gems that have been cut from beryl crystals from Bassett Hill
are colorless or only slightly colored, but quite brilliant, rivaling
the caesium beryl of Maine in luster.
Horse
Hill is mostly stripped pasture land with a generous proportion of
rock outcrops. Three prospects have been found at the south
