riffles.
The parallel riffles are cleaned up at wide intervals of time-All of
the concentrates are further cleaned on a jig operated by a small water
wheel. The concentrates from the jig are oven-dried and shipped for
picking. Gold is also saved from the concentrates. The tailings from
the jigs contain rutile in elongated, much water-worn pebbles, scaly
hematite in quartz, garnet, corundum, pyrite, manganese ore, siliceous
iron pebbles, and other minerals.
The
sapphires from the Rock Creek region are principally used for
mechanical purposes, though some are of good color and quality and of
sufficient size to be cut as gem stones. The prevailing color is some
shade of green, as the yellowish and bluish green of beryl and
aquamarine. Blue, yellow, purple, pink, and red sapphires are found,
however. The greater part of the sapphires are shipped to Switzerland,
where they are cut for use as watch jewels and for other bearings.
COLORADO.
Mr.
C. A. Beghtol reports the discovery of sapphire in the matrix in
Fremont County, Colo., by a prospector named Weston. The latter would
not reveal the locality.
INDIA.
Kashmir.—The production of sapphire during 1906 from the Kashmir mines0 amounted to 2,837 carats, valued at £1,327.
Burma.—In
the operations of the Burma Ruby Mines Company during the year closing
with February 28, 1907, sapphire valued at £1,132 was produced.a The
quantity of sapphire produced is not given separately, but is combined
with that of spinel and ruby, the total of which amounted to 326,855
carats.
CEYLON.
A blue sapphire weighing 466 carats after cutting and polishing is reported to have been found in Ceylon during 1907.6
If the report is true, this is the largest blue sapphire on record, and
if the stone is of good color and free from flaws it should be worth
several thousand
dollars.
AUSTRALIA.
Queensland.—The value of the sapphire production of the Anakie field during 1907 is given at about £40,100,c
as compared with £18,000 in 1906. The miners sell their sapphires to
resident dealers/ who in turn ship them to merchants in Europe.
Probably 75 per cent of the stones go to Germany. The average price per
ounce paid for sapphires during the last five years has been
approximately as follows: 1903 and 1904, 15 shillings; 1905, 15
shillings to £1; 1906 and 1907, £1 4s. The sapphires are graded into
three classes—first-class blue, second-class blue, and " machine
stones," named in order of their value. The use made of the "machine
stones" is not definitely known, though it is supposed they are applied
in mechanical apparatus.
oRee. Geol. Survey India, vol. 36, pt. 2, 1907.
tManuf. Jeweler, November 7,1907; from London Standard.
cMining Jour., London, March 14,1908.
d Mining Jour., London, February 22, 1908.
