FELDSPAR GEMS.
AMAZON STONE. CALIFORNIA.
Mr.
Joseph Ward, with headquarters at both Barstow and Lone Pine, Cal.,
sent to the Survey a number of specimens of amazon stone which he had
collected in the deserts of California somewhere between those two
places. The material consists of many fragments and crystals which
range from small sizes to an inch in thickness. A few of the specimens
show especially good shades of bluish green and greenish blue, with
fairly smooth, fine texture. The associated rock sent with the amazon
stone consists of pegmatitic granite such as is found around the walls
of miarolitic cavities in granite. If crystals of larger size and of
the same good color can be obtained in quantity, the locality should
prove of value.
MAINE.
Specimens
of amazon stone were received from Mr. F. H. C. Keyn-olds, of Boston,
Mass., which had been found during 1914 along the coast of Maine. The
exact locality from which these were obtained has not yet been made
public by Mr. Reynolds. The discovery was made late in the fall, so
that little prospecting was possible and only about a pound of crystals
was obtained. The material sent to the Survey contains a specimen of
biotite granite grading into pegmatitic material, such as is commonly
found lining the walls of a miarolitic cavity in granite. The feldspar
grades from white or gray where it is attached to the granite into
bright bluish-green and greenish-blue amazon stone. The specimens
submitted are rather small, but would cut into cabochon gems of
pleasing color, and if larger masses of equally good quality are
obtained, the deposit will be of interest to the New England,
semiprecious stone trade.
NEW YORK.
Prof.
Freeman F. Burr, of Barnard College, New York City, submitted to the
United States Geological Survey several crystals of amazon stone which
he had collected in a quarry 2 miles northeast of White Plains, N. Y.,
along with information regarding the locality. The quarry is worked for
materials for use in the construction of Kensico dam for the New York
City water supply. Prof. Burr states that about 100 pounds of specimens
have been carried away from the quarry and that probably a large
quantity of equally good mateiial has been sent through the crushers,
along with other rock, for use on the dam. The crystals are described
as varying from less than an inch in thickness to one which measured 7
by 7 by 5 inches. This crystal has been placed in the collection of
Columbia University. Some of the crystals are fairly well developed;
others have but few faces. The quarry is in the Yonkers gneiss, of
pre-Cambrian age. This gneiss is a foliated granitic rock which
contains pegmatite injections. The amazon stone orystals have
evidently come from miarolitic pockets in this gneiss with pegmatite
lining their walls. The crystals are microcline, grading from
flesh-colored bases or interior
