The Sumpter miner. [volume] (Sumpter, Or.) 1899-1905, 1902-09-17
TELLURIDE OF GOLD.
Some Facts About This Rare
Combination.

that tellurium has been discovered In
Malheur county, and there Is no reason
to doubt that this rare metal exists In
other sections Of the state Of Oregon,
THE MINER gives the following facts con.
cerning this substance which may be Of
use to prospectors and others.
Tellurium WIS first discovered ny Mul.
Ter Won Reichcnstein in 1882. 1t IL n sill
ver.white resplendent metal Of markedly
crystalline structure, the crystals being
rhombohedra. From the date of its
first discovery until about the year 1915,
tellurium was considered rare metal.
In the year mentioned II number Of de.
l'osits were found in Boulder county,
Colorado, or, to put II more clearly, II
was in that year when science deter
mined that n peculiar ore found by pros.
pectors In the section named was In
reality tellurium.
Its discovery came about in peculiar
manner. For long time 1t puzzled ~.
sayers and others, and for a while even
the territorial geologist was in II guam
Diary how to determine what IL was. II
had long been the custom Of prospectors,
while travelling from the plains to the
Snowy range, near the summit OF the
Rockies, to camp on what was after
wards known as the Boulder county
telluride belt. Often their camp fires
would be kindled alongside the outcrop
Of telluride vein. Frequently It would
be noticed that gold blistered out OF the
rock, occasioned by the heat Of the fire.
Samples Of this rock when tested by an
assayer failed to show trace Of gold.
Neither could the territorial veologist at
first secure any results, but, occupying
the position he did, it was necessary for
him tO solve the problem. The result
was that hitherto uncommon com.
pound was found TO exist-telluride Of
gold.
Previous to this time II was presumed
that in nature, gold, no matter wha:
metals or minerals II may have been
associated with, was always there in
metallic form, and to this day gold IL not
known 10 exist ~ compound with any
other metal or mineral except telluriun.
When this fact was demonstrated, other
problems arose. Telluride ores could
not he sssayed by the fire process like
ordinary ores. Experiments finally
demonstrated that tellurium was very
volatile metal; when combined with
gold, in the process Of assaying it would
volatilixe and carry the noble metal with
il. The assayer may have had u sample
very rich in gold, but his cupel would
not show trace. These obstacles v ere
finally overcome, however, and any as.
sayer should be able to make as accurate
test for gold combined with tellurium
AZ he would Of any ordinary ore, where
the yellow metal il associated with other
metals or minerals.
During the telluride excitement In
Boulder county, over Il quarter Of u CEN
tury ago. the writer has seen many
prospectors lay a small piece Of telluride
ore on a stove, with buta moderate heat,
and in few moments the gold would
blister out on the surface OF the rock.
Should any Of our readers desire to make
this simple test, it is well tor them to
remember not to use an excessive heat,
as that may evaporate the tellurium too
rapidly and thus carry away the gold.
In smelling such ores great care must be
exercised or the same loss will occur
from. the smelter furnace that did from
the assayer's crucible when little was
known of this element.
There are three kinds Of telluride ores