S. Dana. These were handsome enough to furnish ornamental objects, small balls ι or 2 inches in diameter, charms, etc.
Aquamarine
has been found in a number of localities in the United States, the
principal among them being Royalston, Mass. ; Acworth, N. H. ; Grafton,
Vt. ; Burke County ; Stony Point, N. C. ; Paris, Me. ; Fitchburg, Mass.
; and Avondale, Pa. The richest colored gems from any known locality
have been found at Royalston, Mass. Although small, they are almost as
blue as sapphire. Large, clear gems of light-blue and sea-green tint
have been found at Acworth, Grafton, and Stony Point; at the latter
locality shading into beryl-emerald. The crystals of beryl found
associated with phenacite on Mount Antero, Chaffee County, Col., are
obtained at an altitude of from 12,000 to 14,000 feet, and vary in size
from 1 to 4 inches in length and from 1/10 to 1 inch in diameter. As
crystals, they are remarkable for the fact that portions of them have
been entirely dissolved or eaten away, which gives them a peculiar
etched appearance. In a number of instances not only have the ends of
the crystals entirely disappeared, occasionally leaving long,
needle-like projections, but holes have been eaten through the crystal.
In color they vary from a very light-blue to quite a dark sky-blue,
almost as rich as some of the finest Brazilian crystals. They would
furnish gems up to 10 carats in weight, the largest one cut weighing 5
carats.
A
variety of blue beryl, called goshenite, occurs at Goshen, Mass., in
pieces transparent enough to afford gems. Chryso-beryl occurs in
orthorhombic prisms, and frequently more or less modified as shown in
Fig. 3. Its hardness is 8.5, next to that of sapphire, and its specific
gravity is from 3.65 to 3.85. In color it varies from yellow or
golden-yellow through brown and green, including a large series of
sage-green and leaf-green, as well as rich brown. Alexandrite is the
variety of chrysoberyl that is colored by chromium. It is, by natural
light, of a deep leaf or olive-green color, but by candle-light appears
a raspberry or columbine-red shade. The true cat's-eye is a variety of
chrysoberyl that owes its chatoyancy to minute internal striations
