weighing
up to 30 carats each, and sometimes single stones showing two or three
distinct colors. The new gem mineral, kunzite, had the best display yet
shown at any exposition. Another recent discovery in gem stones was
shown in the fine topaz crystals of light-blue color from liamona and
Valley Center, San Diego County, the best topazes that this continent
has produced. The beryls from the same region are also very
interesting, one of the rarest varieties being pink beryl, found both
at Pala and Mesa Grande. All these minerals were reviewed in the report
of this Bureau for 1904, in the section on the gem minerals of
California.a The special exhibit made by San Diego County attracted much attention and received a first-class gold medal.
As
to the neighboring western States and Territories, a rich display was
made from Arizona of the beautiful malachite and azurite specimens from
the copper mines at Bisbee, Clifton, and Morenci ; also of the elegant
chrysocolla, coated with transparent crystals of quartz, from the Globe
mine. Fine examples were shown of peridot (chrysolite) from the lately
discovered locality for this mineral at Talklal, Ariz., one of these
being a cut stone of 25-3/4 carats. Turquoise matrix, from Gila County,
is a somewhat novel ornamental stone, the rock, traversed by small
veins of turquoise, being cut and polished so as to produce a pleasing
effect. Another ornamental stone, representing lapis lazuli and like
that celebrated mineral adapted to choice uses in art work, is dark
blue fibrous dumortierite from Clip, Yuma County, Ariz.
New
Mexico was represented by specimens of turquoise and of the pyrope
garnets from the Navajo nation, which are often miscalled rubies.
From
Utah was shown the elegant green mineral utahlite, from the Floyd
mining district in Clay Canyon. This substance is found only in Utah.
Wyoming was represented by fine pieces of moss agate in large polished slabs, from Hartville.
Among
the most valuable gem materials shown from Montana were the beautiful
blue sapphires from Yogo Gulch, Fergus County, which present a striking
contrast to the varied colors of the sapphires found in the placer
washings near Phillipsburg. Granite County. These latter are all
obtained by sluicing, whereas in Fergus County sapphire is mined in
solid igneous rock. Montana was also represented by some remarkable
examples of amethyst and of smoky quartz found a few years ago in the
Little Pipestone district, in Jefferson County.
The cut stones in the exhibit numbered altogether 90, and the uncut specimens 129, a total of 219.
Gem gathering in Ceylon.—Mr.
A. K. Coomeraswamy, director of the mineral-ogical survey of Ceylon,
has published a paper on the rocks and minerals of that island,b
with special reference to the gems that have been gathered there from
time immemorial. In the Report of the Mineralogical Survey for 1904c an
extended account is given by Mr. Coomeraswamy and the assistant
director, Mr. James Parsons, on the " gemming " industry of Ceylon. The
gems of the island are all obtained from a widely distributed gravel or
Warn, with the exception of some garnets and the valuable
Ceylonese moonstone, which latter is taken out by quarrying from an
adularia-bearing leptynite, in the central Province. The gravels are
now worked by washing in the Ratnapura district of Sabar-amamuwa
Province and in parts of the southern Province. Elsewhere they appear
to have been exhausted, and the same fate is steadily approaching the
regions that are still productive.
