A
small amount of work has been done on the land of James E. Bowker
adjoining the land of Mount Mica Co. on the east. There is a good
outcrop of the pegmatite on this property, and the reported results of
the little work done would justify further development. Pockets with
fine green gem tourmaline were found with the same association as in
the main quarry.
A
number of quarries have been opened for feldspar and gems on Mount
Apatite, about 3-1/2 miles west of Auburn, Maine. The early work was
sporadic and chiefly in the nature of prospecting for gems, but in 1912
the Maine Feldspar Co. reopened some of the old prospects and started
new work for feldspar. Other parties have also supplied feldspar to the
Maine Feldspar Co. and have handled the gem and specimen minerals
themselves. Some of these are E. Y. Turner, J. S. Towne, P. P.
Pulsifer, and H. U. Greenlaw. The Maine Feldspar Co. and the Greenlaw
quarries are on the east side of Mount Apatite, the Turner and the
older workings on the south side, and the Towne and the Pulsifer
quarries on the west side.
As
far as seen the whole summit of Mount Apatite, where opened by
quarries, is composed of pegmatite, but the relations of this rock to
the country rock are not exposed. Bastin 1 gives evidence tending to show that the pegmatite is a large flat-lying mass occupying the summit of the hill.
The
Maine Feldspar Co. has worked several quarries for feldspar to depths
of 5 to 25 feet, and one quarry to nearly 50 feet in depth. Occasional
pockets with gem tourmaline have been found in some of the quarries,
and in places the surrounding rock carries colored tourmaline. The
majority of the gem tourmaline was found in earlier days by N". H.
Perry, Thomas F. Lamb, and other people prospecting on the old Hatch
farm on Mount Apatite. The discoveries of gems by the Maine Feldspar
Co. have not been especially important. The tourmaline crystals found
during earlier mining are described by G. F. Kunz 2 as
colorless, light pink, light blue, light puce-colored, bluish-pink, and
light green, and at times nearly all these colors are found in one
crystal. E. S. Bastin 3 states that later work by Thomas F.
Lamb yielded tourmalines which cut into gems of nearly emerald-green
color. Still later work by the Maine Feldspar Co. on the east side of
the top of Mount Apatite developed two gem-bearing pockets from which
deep-blue indicolite crystals with a greenish tint were obtained. M. L.
Keith, of Auburn, cut some gems of fair quality from them. In another
quarry of this company on the east side of the hill, no gem pockets
were found, but considerable massive beryl was obtained from the solid
pegmatite.
Three
quarries have been worked on the land of H. U. Greenlaw on the east
side of the top of Mount Apatite, and at one of these, adjoining one of
the quarries of the Maine Feldspar Co., a quantity of dark-pink
lepidolite, talcose-like altered pink and blue tourmaline, cookeite,
and other alteration products of original lithia minerals are found.
Small pockets with a few colored tourmaline and a pink beryl crystal
are reported to have been opened here during the summer of 1913.
> Geology of the pegmatites and associated rocks of Maine: U. S. Geol. Survey Bull. 445, p. 53,1911. 2 Ob the tourmalines and associated minerals of Auburn, Maine: Am. Jour. Sci., 3d ser., vol. 27, pp. 303-305,1884. » Op. cit., p. 52.
