56 PEGMATITES AND ASSOCIATED ROCKS OF MAINE.
to
1-1/2 inches across; many of its curved crystals arc interlaminated
with the bladelike crystals of snow-white clerelandite or are partly
embedded in light-gray, more or less transparent quartz. Amblygo-nite
occurs in the solid pegmatite in irregular masses, some of them 6 to 8
inches across. Some small crystals of columbite, cassiterite, and
rhodochrosite occur, but their crystal faces are usually only
imperfectly developed. One crystal of zinc spinel of perfect form,
five-eighths inch in diameter, was found embedded in the feldspar. At
the time of the writer's visit only two gem-bearing pockets had been
found. One of these bore dark grass-green tourmalines and the other
light-green tourmalines tipped with opaque pink. The largest of the
dark-green tourmalines was about three-fourths inch in diameter and
1-1/2 inches long but was badly flawed. A number of other
pockets bore only crystals of transparent quartz. Some fine specimens
of berderite have also been found at this locality. This mineral occurs
in short prisms, few of them over one-fourth inch long, commonly as an
incrustation on the quartz crystals of the pockets. One short stout
crystal attached to muscovite was as large as the end of one's thumb.
This mode of occurrence is similar to that observed at Stoneham, where
it was first discovered, and there can be little doubt that it was
formed through gaseous or aqueous deposition after the solidification
of the main pegmatite mass.
The
feldspar obtained at this locality is hauled 2 miles for grinding to
the mill of the Maine Feldspar Company. The gem tourmalines are cut and
sold, principally in Maine, by Mr. Towne.
Wade and Pulsifer gem quarries.—A
pegmatite mass located on the farm of P. P. Pulsifer, within 100 yards
of the Towne quarry, was opened up in 1901 and was worked
intermittently until 1904 for its gems and other rare minerals.
The
quarry was visited by the writer in August, 1906. The original pit,
opened by Mr. Pulsifer in 1901, is about 25 by 25 feet and S feet deep;
it connects with another pit about 75 by 30 feet, with a maximum depth
of 8 feet. The mineral rights at this second pit were acquired from Mr.
Pulsifer by the Maine Tourmaline Company, and were worked in the
summers of 1904 and 1905.a The two pits constitute virtually a single quarry.
The
rock at this locality is practically bare, so that little or no
stripping is necessary in working the deposit. The pegmatite is similar
in general character to most of the gem-bearing pegmatites of the
State. The main mass of the rock is a graphic intergrowth of quartz
with orthoclase and microcline, showing abrupt variations in
coarseness. The deposit as a whole seems to be rather flat lying, as is
shown by the presence near its base of a nearly horizontal
