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1064
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MINERAL RESOURCES.
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majority
is rather inclined to grayish pink, and some is greenish gray. Both
finely granular and rather coarsely crystallized rhodonite occur. The
different colors and textures grade into each other and with the black
seams and markings would yield contrasting ornamental material. The
purer pink varieties, with or without the black seams, could be cut
into very pretty gems.
OREGON.
Specimens
of rhodonite with information on the occurrence have been received from
Mr. C. H. Gillette, of Ashland, Oreg., from a deposit near the
Josephine County caves. The rhodonite is associated with black oxides
of manganese below a limestone formation. The specimens sent were
obtained during prospecting for manganese and had been badly fractured
during blasting. The rhodonite is delicate rose pink, and with it is
associated gray and a little greenish-gray mineral, also probably
rhodonite, and manganese oxides. The texture is very fine grained,
nearly compact, so that the material ought to take a good polish. The
combination of colors would yield pleasing gems.
SAPPHIRE.
MONTANA.
A
large production of sapphires was reported from Montana during 1911.
The output came from the Yogo blue sapphire mines in Fergus County;
Eock Creek, in Granite County; Dry Cottonwood Creek, in Deerlodge
County; and the Missouri River placers east of Helena. The mines
operating in Fergus County were the New Mine Sapphire Syndicate and the
Yogo American Sapphire Co. These companies obtain sapphires by mining,
disintegrating, and washing a rock matrix. The sapphires obtained here
are nearly all blue; those from the other localities are varicolored,
and fine blue stones are rare. The Yogo American Sapphire Co. commenced
operations in July, 1909, but as no report was received by the Survey
the output of this company was not included in the tables of production
for the years 1909 and 1910. Mr. H. O. Chowen, president of the
company, has supplied statistics of production for the last three
years, and this total output is given combined with that of other
producers for 1911 in the subsequent table. Consequently the figures
given for 1911 are a little high, but the great increase over 1910 is
also in a large part due to increased productions from other mines.
The
output of the New Mine Sapphire Syndicate was also greater than in
1910. Some fine sapphires are reported to have been found at this mine
in 1911, two of which were exceptionally good. One of these weighed
3-1/2 carats and the other 2-1/2 carats and both had a
beautiful cornflower-blue color. The summer season, in which the
washing is done, was better than in 1910, and no cloudbursts occurred
to damage the ditch on which water for washing is dependent. The water
supply was plentiful and together with the new depositing floors laid
down in the previous summer added to the increased production of gems.
The
sapphires mined from the other localities mentioned all occur in placer
gravel deposits. On Dry Cottonwood Creek some have tbeen mined by
dredging, and one dredge was operated by the Consoli-
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