CHRYSOCOLLA. CALIFORNIA.
Mr.
William V. Holley, of Los Angeles, Cal., gives an account of a
combination of richly colored copper minerals found at Cima. in San
Bernardino County. Chrysocolla, azurite, and malachite are here mingled
in compact size, so that the whole may be cut and polished, showing
various shades and patterns of blue and green in beautiful manner well
adapted to use in ornamental work.
DUMORTIERITE.
The
rare blue mineral identified in 1879 by Gonnard and named by hi:n
dumortierite, has lately been found at two new localities on the
Pacific coast, and is made the subject of an extended discussion by Mr.
\Y. T. Schaller, in Bulletin No. 202 of the United States Geological
Survey." In the report of this Bureau for 1892 the announcement was
made of the notable occurrence of dumortierite at Clip, Yuma County,
Ariz., where it so fills masses of quartz as to resemble lapis-lazuli,
and reference was also made to another locality in Riverside County,
Cal., where it occurs in the same way. as fibers penetrating and
coloring quartz. This was more fully described in the report of 1893.
but nothing seems to have been heard since then of this latter
occurrence.
California.—Within
a year or two past dumortierite has been found in larger quantity and
of a different tint in San Diego County, Cal., a few miles east of
Dehesa, the place noted for its "orbicular diorite." Here it appears in
masses of several centimeters in either direction, with a radiating
columnar structure and of a pinkish lavender color, instead of its
usual indigo blue. It occurs intermingled with quartz in the lower half
of a large dike, the upper half of which contains sillimanite, instead
of dumortierite. similarly associated with quartz.
Washington.—Another
locality lately announced is in Skamania County. Wash., at the
headwaters of the North Fork of Washougal River. Here the form is
different again, the mineral being present in minute spherulites
composed of radiating fibers of strong blue color. These are
distributed through a fine-grained quartz matrix as blue specks,
sometimes massed in patches and sometimes abundant enough to color the
whole mass. Associated with it is andalusite. apparently taking the
place of the closely related species sillimanite at the previous
locality.
"Contrib. to Mineralogy: Bull. U. S. Geol. Survey No. 202, 1905, pp. 01-li!0.
