Santa Fe new Mexican. [volume] (Santa Fe, N.M.) 1898-1951, 1900-08-01
A new. CONCENTRATION
The Dimmick Brothers Installed a Plant at
the Helen Mining 0~ompany's Mines
at Graham.
A METHOD THAT SAVES Big VALUES

n MHluVU luhl Nh Dlu IhuUhl
The Dimmick Concentrating Com
pany was recently incorporated in Den.
Equitable building at that city. It's of
ficers are Joseph o. Dimmick, presi.
dent; Fred w. Feldwisch, vice presi.
dent, and John T. Graham, secretary
and treasurer. This company was in
corporated to handle the Dimmick siZel
n classi1er and the electromagnetic
concentrating table, patents for which
were recently secured by Joseph o.
Dimmick, who is the inventor of these
new methods of concentration. The
Dimmick sizer and classifier, upon
which Mr.. Dimmick secured a patent
but a few days ago, is destined to rev.
o%lutiOnize the methods now in use in
connection with concentration. 1t con-
sists of a new and improved device for
sizing and classifying the pulp from
quartz mills, as preliminary prepara-
ton for first concentration by water,
and subsequently for extracting the
coarse waste silica and sand, reducing
the volume of water contained in the
pulp solution by passing off the surplus
in a clear state with no loss of shines
or fine values, thus reducing the mill
tallings to the smallest possible
amount, containing all the fine values
with just the requisite water for sec
ondary concentration and recover of
such values. BY the methods now in
vogue, when milling by stamps or other
methods of pulverization, the pulp dis
charged through the screen has a great
range in fineness and specific gravity
Of the particles. When the entire prod
uct has passed directly to any concen-
trating table it. must be evident that
sufficient water to move the coarser
particles of waste from the separating
surface of the machine and permit a
separation of the coarse mineral must
necessarily carry the finer particles of
mineral along with the flowing water
and waste material, and they pass off
and are lost. Consequently, the first
condition to be aimed at should be to
separate the pulp into classes. Mr..
whose long practical expe-
rience in connection with concentrating
methods peculiarly adapted him to a
work of this kind, decided that these
fine values could not be saved until
device had beer invented espe-
cially adapted to this purpose. After
failures he hit upon the under
sizing in a specially arranged V tank |
to take off first the oarse sand and let |
It run away, as the coarse concentrates |
hat would naturally flow with it had |
all been extracted in the first concen-
Therefore, it was desirable to
get clear of it, instead Of passing it
again over the tables. Then to gather
he fine values in the water into a
loser consistency of mineral and wa
er, by submersion and suction, leaving
he water at the surface, at the point
# overflow from the tank, in a clear
tate, and the arrangement and work
ng such that the desired quantity of
could be drawn off at the over
low without loss. Thus the product
arried to the tables being greatly re-
uced in quantity and the percentage of
mineral contained with 1t largely in
the problem was reduced to
asy, rapid and effective solution, with
proportionately less number of ia
labor and expense. This tank, I'M
.rsizer and classifier performs ali this
reliminary work rapidly and effective
at a very insignificant cost, as when {
nee In operation, with draughts and
verf1ow properly adjusted so as to pro-
uce the classification desired, and re-
uction of water to the amount neces- I
iry to be used, the operation is au-
'm~atically regulated and continuous, !
nd requires little OF no attention or
Ipense. The Dimmick Concentrating {
1mpany has recently installed a plant s
some Of the Moffatt- Graham 4
'operties, those of the Helen Mining
ompany at Graham. The plant treats
e accumulated tailings from their sill
r. mill, also the tailings now being J
scharged from the mill direct to the A
ger; and each size passed over the A
electromagnetic concentrating tables. A
1ese tailings carry a very light sui A
lide, and considerable Toured quick A
yer lost from pan amalgamation in q
e mill. These values are very diff n
1t to recover, and many experiments r
We failed to give satisfactory results. F
reful panning tests upon the average B
these tailings produced a concentrate q .
an average Of $26 per ton, So %,
: cent of this value being golds bal W
&c, silver, and only a portion Of the ~,
Icksilver being recovered which was !,
t in the fire assay. The results OBJ a.
ned from the Dimmick Concentrat- a,
Company's plant showed far better 4,
ults than those obtained by the PAN
the average value of the product
fire assay being $64 per ton In gold
silver for each ton of concentrates va
overed, 4S per cent of this value be-
gold, balance silver. Amalgamation
8 of ten-ton lots of the concen- w,
.es effected a recovery Of 1851
ndS of quicksilver and Sh0 IN Uo1d