The Salt Lake tribune. [volume] (Salt Lake City, Utah) 1890-current, 1912-03-29
DISCUSSION ON THE
FUTURE OF COBALT
Held That Recent Disclosures
May Add Life TO the
District.
VALUES FOUND DEEP
Not Enough Work Done to-
Lead TO Definite Con-
clusions.
VALUES FOUND DEEP

The orc formations OF Cobalt have been
the source OF an almost endless discus
sion relative 10 the probable life Of the
district and the continuity OF values with
depth. In view OF some OF the late
discoveries made in properties which
are extensively developed and the light
shed upon ore occurrences. Mining
Science gives n summary OF the results
which NAV be expected In the future.
as follows:
The association ~ variety OF silver
minerals with arsenides and sulphides Of
cobalt and arsenic is unusual. though not
unparalleled. Their mode OF occurrence
Is equally interesting. ConGlomerates,
grsywaokes, and graywacke states. form
inE the Cobalt series. rest unconformably
garded as keewatin. Both series have
been intruded By a sill OF quartz -diabase.
which Is nearly horizontal in some parts
Of the district, but steeply inclined in
others
AS soon as development Of the mines
had proceeded far enough TO furnish evil
dence. considerable differences OF opin
ion developed TO tho nature and
origin of these deposits. which have been
nearly all OF the more prominent eco
nomic geologists. the most extensive work
having been done by ". G. Miller. pro-
vinciai geologist OF Ontario. and his as
TO field studies has in conjunction with
w. c. Campbell. made detailed petro-
graphic studies of these ores
Prevalent Theory.
The most generally accepted opinion.
II any one may be regarded as of gem
eral acceptance. Is that ore-bearing fis-
sures. due TO contraction upon cooling
after the intrusion Of the dlebsse. have
been filed by uprising solutions subse-
quent To the intrusion. The dlabase and
the everything cobalt series was naturally
more. fractured than the generally un-
early reached that the assures would eX-
tend TO no great depth. tending 10 dis
appear In the keewatin. and early de-
velopnent tended 10 confirm this gen
eralzation which. in the form of an
amusing verse. gained wide publicity.
With later work, increasing numbers
Of veins were found. both In tho diabase
and In the keewatin. and recently, as re-
corded In our Toronto letter. the No. Q
vein in the Contagas has been proved not
only to persist: but also 10 be profitable
in the keewstln. Apparently the pros
poets in depth are not so hopeless as was
at 6rst supposed
Another View.
Another view as TO the origin of these
deposits was held by the late 8. 4. EN-
mons. who in a notable paper published
in this journal shortly before his death,
advocated the hypothesis that the veins
occurred in fissures of the ordinary type,
their small size being due 10 their repre-
sentinS only the roots" as 1t were. OF
larger veins formed in great thickness
OF overlyng rocks. With this concep-
lion as a basis IL Is easy 10 ascribe the
phenomenal richness of the veins to sec
ondary concentration during erosion.
This view also leads to q pessirnsiic
outlook as TO the orc content of the
keewatin rocks. One swallow does not
make a summer. and few veins traced
short distance into the keewatin can
not be assumed. after the fashion of pro-
moters. TO indicate that the ores extend
10 the ewige tiefe, but the outlook is
st least now mora hopeful.
a district which has one producer Of
$500. 900 ounces OF silver annually. a sec
ond Of S.750,000. and a third OF nearly
1000. 900 ounces. has established place
for itself among the great districts of
tho world, even II II should be subject
TO too early decline.