land;
also, a series of nearly one hundred crystals from the same place,
collected by the late Prof. N. H. Perry, and a number of other
crystals from other Maine collections. Harvard University, therefore,
now possesses the finest known series of colored tourmalines in the
world.
A new locality for pink tourmaline is given by Mr. Orcutt in a report on the minerals of the Colorado desert.(a) It
is found in the mountains of Lower California, south of the Alamo mines
(though whether within the actual limits of the desert or not, he does
not specify), in an identical association with that from Rumford,
Maine, and from Rozena, Moravia, viz, rose-colored tourmalines in
lepidolite.
Quartz.—An
interesting discovery has been made at Placerville, Eldorado county,
California, by Mr. James Blackiston, in a quartz ledge running north
and south and dipping eastward from 45 to 50 degrees. The rock of the
ledge, which is partly decomposed and partly compact, is traversed for
perhaps 100 feet by a vein of crystallized quartz varying in width from
6 inches to over a foot. This vein is also decomposed, and is tilled in
with a reddish earth or sand and can be dug into with a stick or board.
It was full of quartz crystals of all sizes, from that of a man's
finger up to large dimensions, some of the crystals weighing as much as
SO or 90 pounds.
Several
of these, over 50 pounds in weight, were pellucid and free from flaws;
while others have peculiar interest from remarkable inclusions of
chlorite, 3 to 5 millimeters in thickness, at several depths in the
crystal, thus marking successive stages of crystal growth and making
very striking " phantoms," generally of green chlorite on white quartz
layers. Of still greater interest, however, are other quartz crystals,
2 to 4 inches in length and half as much in diameter, containing at or
near their centers inclusions resembling groups or clusters of
dolomite or siderite crystals cream-white to brown in color, and
consisting of many curved rhombohedra from 2 to 4 millimeters in
diameter.
Quartz
crystals containing inclusions of goethite crystals, have been found in
the Tarry All range, 40 miles west of Colorado Springs, and cut into
beautiful ornaments resembling quartz penetrated by crystals of black
rutile.
Smoky quartz.—Pine
crystals of smoky quartz, one of them 3-1/2 inches in length and If
inches in diameter, have been found in Three-Mile gulch, 3 miles
southeast of Helena, Montana.
Hydrolites.—Thin
shells of chalcedony filled with water and containing a moving bubble,
measuring from 1/2 to 1-1/2 inches in diameter, are frequently found on
the Oregon coast near Yaquina bay and Astoria.
In
a report on the minerals of the Colorado desert, Mr. C. R. Orcutt
mentions " water-agate" (hydrolite) from Canyon Springs, and beautiful
agates and chalcedonies in the drift of the desert and scattered over
the mesa-like formations that border the depressed plains. a C. R. Orcutt, Tenth Annual Report of the State Mineralogist of California, 1890.
