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CHAPTER IX.
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Feldspar Group.
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T
HE greenish variety
of orthoclase named lennilite by Dr. Isaac Lea ' is found at Lenni
Mills, Delaware County, Pa. The pearly variety found at Blue Hill, two
miles north of Media, and called by Dr. Lea dela-warite, is a
bluish-green, sub-transparent cassinite, of an aven-turine character,
the bright particles being hexagonal hematite, and often fine enough in
color to make a gem or ornamental stone. Elseolite has been found at
Magnet Cove, Ark., in very compact nodules of rich flesh, cinnamon, and
yellow-brown color, and in such abundance as to warrant its use for
certain purposes in jewelry. That found at Gardiner and Litchfield,
Me., admits of a very good polish, the color being greenish and of a
good appearance, while part of that found at Salem, Mass., is also
valuable. (See Cancrinite and Sodalite.) At Van Arsdale's Quarry2
near Feasterville, Bucks County, Pa., orthoclase is found in crystals
from 1/2 an inch to 2 inches in length, usÂually, however, in cleavage
masses of a gray or grayish-black color, which show the blue chatoyancy
finely and make a very fine variety of moonstone. The beautiful
specimens of albite found at Mineral Hill, near Media, Delaware County,
Pa., show
1 Am. J. Sci. III., Vol. 36, p. 326, Nov., 18S8. s Preliminary Report on the Mineralogy of Pennsylvania (Harrisburg, 1875). p. 89.
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163
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