of
such a deposit is to wash at least 50,000 cubic yards of rock with the
proper type of washing machines. Small test runs on certain parts of
the peridotite outcrop indicate at least a content of 0.21 carat per
load of 16 cubic feet. The possibilities of cheap mining in Arkansas
are great, since there is an abundant supply of water and timber near
by and coal should be obtained at reasonable rates.
Mr.
Stifft, of the Stifft Jewelry Company of Little Rock, Ark., reports
that over 700 diamonds have been found up to July 1, 1909.
According to reports a the
Ozark Diamond Mining Company, of Little Rock, has taken up the Mauney
property, covering 8 acres of the peridotite outcrop adjoining the land
of the Arkansas Diamond Company, and is engaged in prospecting it. A
number of diamonds, are reported to have been found.
The discovery of a new peridotite deposit in Arkansas has been described by A. H. Purdue.6 This deposit is located a little over 2-1/2 miles
northeast of the original area and 3 miles south of east of
Murfreesboro. It was discovered by M. N. Burgess, of Murfreesboro. The
peridotite outcrops on the north slope of a hill whose top is covered
with 10 to 12 feet of "plateau gravel" cemented into conglomerate. The
gravel debris covers portions of the hill slopes and, along with the
depth of soil and vegetation on the latter, renders it difficult to
determine the boundaries of the peridotite. The peridotite covers at
least 2-1/2 to 3 acres of land, though the actual area may be found to be still greater.
From
macroscopic examination this peridotite appears to be identical with
that of the original area described by Kunz and Washington.a
The rock weathers readily, and on the outcrop has disintegrated into
soil and bowlders up to the size of a man's fist. The soil is green,
brown, and yellow according to stages of oxidation. Rather hard
fragments of peridotite thrown out of pits go to pieces after a few
days' exposure. The formations cut by the peridotite are referred most
probably to Cretaceous age, and the peridotite is probably synchronous
with the peridotite of the original area. In the original area more
resistant portions of the peridotite have withstood weathering and
have formed knobs and elevations extending in a northeast-southwest
direction. The new area lies in this same general line.
This
new peridotite area has been taken up by the American Diamond Mining
Company, and prospecting work has beenstarted. Reece Lamb,
vice-president of the company, reports that seven diamonds have been
found, along with several garnets and numerous quartz crystals.
California.—The
United States Diamond Mining Company has continued prospecting work on
its property near Oroville. According to reports the shaft is 180 feet
deep, and several small diamonds and chips have been found. As yet no
authentic report of these finds has been received at the Survey.
Kentucky.—Press
reports indicate continued prospecting in the peridotite areas of
Elliott County, Ky., during 1908. Reports state that two diamonds have
been found, though details and official confirmation of these
discoveries have not been received.
o American Jeweler, December, 1908.
6 EcoB. Geology, vol. 3,1908, pp. 525-528.
c Trans. Am. Inst. Min. Eng. Bimonthly Bull. No. 20, pp. 187-194.
