The Eureka sentinel. [volume] (Eureka, Nev.) 1902-current, 1922-09-30
POSSIBLE SODIUM INDUSTRY FOR EUREKA COUNTY

A new deposit Of sodium sulphate
mas been discovered In Nevada during
the past Summer. 1t lies within Dia-
mond valley, near the center of the
state, rs miles northeasteriy from
Eureka. at an altitude Of 5000 feet.
The deposit is Of exceptional pur-
ity. being almost free from sodium
chloride, carbonate, iron. or other de-
leterious substances. The available
tonnage has been fully ascertained.
and thorough exploration of the
promising areas shows a total pros
pective tonnage of 10000 tons, or
an amount sufficient to operate a So
ton mill about eight years. Tonnage
Is conservatively estimated, and the
final available anount may easily ex-
coed the figure given. The property
is being explored by San Francisco
capital.
OCCURRENCE OF DEPOSITS
The sulphate occurs in dIsconnect-
ed ponds near the edge of Diamond
Valley. about four miles from the
nearest foothills. Ponds vary in size
from 80 feet across to maximum
areas SO0x1200. The ponds ordinarf-
ly occur within less than 1000 feet
from one another, and exploration
has shown that the deposits in the
ponds do not extend laterally be-
meath the valley wash.
ularly around the larger ones, the
wash Is ridged up from two to eight
feet above the valley floor. These
ridges generally slope steeply on
their inner sides. towards the ponds.
and grade on almost imperceptibiy.
on their outer sides. into the valley
floor. The highest ridges occur
around the largest ponds, and near
their deepest portions.
The suiDhate deposits are crystal
line and transparent. and in appear
ance resemble ice. AS a rule the sui
phate shows clearly at the surface.
but locally 1t is covered by two to ten
inches of soft, white-coated mud.
Within a given pond the sulphate
may occur both as large. solid masses
and as irregular cakes OF varying
size. The solid masses are up to
400x5OO feet In snrface dimension,
and 80 to so inches thick. The cakes
are rarely more than 100 feet In max
imum length. or more than As in
ches in maximum thickness. They
are commonly but little thinner at
the edges than In the center, and In
appearance resemble irregular cakes
Of ice not quite submerged in a mat
rix of soft mud. In the cake areas
mud constitutes from 20% to 40%
OF the volume.
Thus far no clearly defined under
lying layers OF suiphate have been
found beneath the deposits exposed
at the surface, but crystals OF the sui
phate up to three or four inches in
length occur promiscuously in the
underlying mud.
METHOD OF EXPLORATION
Exploration has been done by
means of jumper drills. These drills
chip a uniform 3h In. hole through
the deposit, and all cuttings aresaved
and assayed. In the solid masses
holes are 100 feet apart. except
around the edges of the masses,
where they are placed as closely as
necessary to determine actual volume
of the body. In the cakes from four
to a dozen or more holes are drilled,
depending on the size and variability
in thickness Of the cakes. In COM
putting tonnage of the cake areas us
ually 5O% of the surface area is de-
Quoted to allow for variations in
thickness OF the cakes not visible
from the surface and not discovered
in drilling.
:, The average analyses of samples,
representing developed tonnage. is:
Water capitalization, 30%; sodium
sulphate. sos; sodium chloride, .5%;
insoluble, $50.
POSSIBLE ORIGIN OF DEPOSITS
The deposits clearly are not old
lake beds. as they are forming at
present and are not interconnected
between ponds. The sodium sui
phate is brought up from beneath by
ground waters much after the man
ner of mud springs" The follow
ing table, which gives the solubflity
of sodium sulphate at various tenn
peratures, shows precipitating ratio
of ten to one between waters at,ordi-
nary Summer temperature and the
freezing point.
The warm days and cool nights OF