with
the tourmaline. Other recent work consists of a crosscut tunnel on the
south side of the hill, in which good ledge material was located.
Drifts were to be run in each direction on this part of the vein.
Mesa Grande Consolidated Gold and Gem Mining Company.—The
Mesa Grande Consolidated Company is operating a mine one-third of a
mile south of the Himalaya mine. The recent work consists of an incline
about 100 feet deep with drifts and stopes on the sides. Two shafts
were formerly sunk to the northwest with drifts and stopes between
them. The pegmatite varies from 6 inches to 3 or 4 feet in thickness
and strikes northwest with a southwest dip. Mostly pink tourmaline was
being found at the time of the writer's visit. Some of this was
first-quality gem material; other was suitable for cabochon cuts.
Esmeralda and Trail mines.—The
Esmeralda and Trail mines are about a mile and a half north of west of
the Himalaya mine. The Esmeralda mine is evidently on a large pegmatite
formation or on several arms of pegmatite. Considerable work has been
done in the form of tunnels, cuts, and prospect pits. Biotite and black
tourmaline are plentiful in the pegmatite. Beautiful pink and
aquamarine beryl and some varicolored tourmaline have beeen found at
this mine. At the Trail mine, on the same ridge and just above, the
pegmatite carries dark-blue, nearly black tourmaline and much rough
muscovite. Beryl crystals are said to have been found here.
Cota mine.—The
Cota mine is about one-third of a mile southwest of the Himalaya mine,
and the vein consists of a blanket ledge of pegmatite on the hillside.
It is from 2 to 5 feet thick and strikes northeasterly with a light
southwesterly dip. The ledge is banded with several textures, as seen
in one exposure. It contains black, green, and blue tourmaline, with
some of slightly pinkish color. Small hyacinth garnets and a pink clay occur in the vein. The gem minerals occur in streaks or long pockets.
Rose Quartz mine.—The
Rose Quartz mine, on a narrow, high spur or ridge, is 4 miles N. 60° W.
of Mesa Grande. The ledge at this mine is marked by a large outcrop of
pale, translucent rose and white quartz. The pegmatite is probably over
35 feet wide and contains quartz segregations 20 feet wide in places.
Feldspar also occurs in nearly pure masses 6 to 8 feet through. Large
black tourmaline crystals 2 to 5 inches in diameter and several feet
long occur in the pegmatite. The only gem mineral so far found has been
a very dark reddish hyacinth garnet.
RAMONA.
Little Three and Surprise mines.—The
Little Three mine on the northwest and the Surprise mine adjoining on
the southeast are situated near the foot and on the south side of a
hill, 4 miles N. 70° E. of Ramona, on which a number of gem mines have
been located. The pegmatite ledge at these mines has a northwesterly to
north of west strike with a dip of 25° SW. The pegmatite varies from 3
to 10 feet in thickness, a portion consisting of finer-grained, banded
pegmatite. Some of the gem minerals are found in pockets, while others
are frozen in the vein matter. The pockets vary from 1 or 2 feet long
and 2 or 3 inches wide to 20 feet long and 12 to 18 inches wide. The
gem minerals found are hyacinth garnet, topaz of
