Gilpin observer., 1909-08-19
TRAPHAGEN's REPORT.


cred for the successful treatment OF
ores of Gilpin county, has made his
report. This appears in an issue of
the Denver News of the 14th inst,
| together with the following intro.uc-
tory:
THE problems which have long
been an obstacle to the successful
cyanide treatment of Gilpin county
ore concentrates in the extraction OF
gold and copper values, have been
solved by the Draper-Al3dorf process,
according to Professor Frank w.
Traphagen of the Colorado School of
Mines, and the installation CT a 300
ton plant for the treatment of the
product Of the mines in that se.tion.
will place Gilpin county in the frs
rank Of the ssate's producing coun
ties.
The 100000 necessary for the
construction of a cyanide plant en-
bracing the Draper-A,sdorf process
which constitutes the most impor-
tant metallurgical discovery within
the last five years, is practically as
sured. Outside capitalists have offer
ed to finance the proposition, but it IS
the desire of the promoters to have
the control remain at home, and they
are endeavoring to interest the own
ers of those properties from which
70 To ha
make the plant a cooperative one.
Work along this line is beinp sue
cessful.
The saving which the Draper Ais
dorf process, installed in a plant easi
ly accessible by the mines of Gilpin
county, will bring about, will be not
alone in transportation, but penalties
now imposed at various sme,ters.
which seriously impair profits from
low-grade ores.
Professor Traphagen last week ex-
amined the new Gilpin county meth
cd.
There is no insurmountable bar
rier to the cyanidation Of Gilpin coun-
ty ores said Professor Traphagen.
This fact has been demonstrated
by Messrs. Draper, A,sdorf and Weed
after series of painstaking and ex-
haustive experiments.
1t is not be assumed, however,
that satisfactory results were easily
obtained, for the contrary is the fact.
Difficulties which are usually present
in cyaniding problems were not ab-
| sent here, but by application OF
chemical knowledge and careful ad-
justment Of conditions, very satisfac.
tory extractions of the precious met
al values have been made, with
very low cyanide consumption and
cheap treatment costs.
The results have been SO gooi
that every promise of greatly
improved condition in Gilpin county,
following the adoption of this treat
ment, may be counted upon for full
fillment.
Under present conditions little
profit is derived from the sale of con
centrates-in fact, no good concen
trates net the seller as much as con.
centrates ranging up to about s12 OIL
Sl3 in value, the former going to the
manufacturer of sulphuric acid, while
the latter must pay freight, smelling
charges and penalties which are
/ nin
against a low-grade product.
The plan proposed for the treat
ment under the revised scheme o
Draper and Alsdorf, is to amalgamats
then concentrate and cyanide the tail
ings and the resulting concentrates
This scheme of treatment vii
give series of products; amalgama
tion bullion, cyanidation bullion ant
under certain conditions. lead, cor
per and possibly zinc concentrates
and an extracted concentrate contain
ing little of value beyond iron pyrite
which will net 1925 a ton at tn
plant when sold for the manufacture
of acid
Thus practically all Of the valu
in the ore is made to yield profit
and, in consequence. much lowe
grades of ore can be mined. Henc
a marked improvement in the activit
OF the mines of the county may b
expected to follow the adoption c
this more efficient and cheaper pre-
, cess.
, THE 300.ton mill planned for tn
district will undoubtedly be built, fo
, the enterprise has received the SUI
, port II deserves. and We may yer
( soon see the first cyanide plant {