Gilpin observer., 1913-05-15
G|LP|N RAD|UM ORES
To the Editor of the Observer:

To the Editor of the Observer:
Mining Science" May 1913, con-
tains an article under the title, Car
notite as Supply Of Radium", by
Al w. Forstall, of Sacred Heart Col.
lege, Denver.
In this publication, the author en-
deavors to show that carnotite ores
now being mined in Western Coiorae
do, constitute the real source of sup
ply of radium; that this carnotite,
in its qualities relative to uranium
content and associated radioactive
substance compares favorably with
the Austrian pitchblende and leaves
it to be inferred that in no other
direction does it come into competi-
ton with any other ores of uranium
or radium.
The author further publishes i'm sup
port of his views photographs from
carnotite and uranium concentrates"
These photographs are misleading
and the article itself is more re-
markable for what 1T says that ''ain't
so'', than for what it says.
incidentally, though residing with
in sight of the hills behind Central
City, where pitchblende is being min
ed, Mr.. Forstall makes no mention of
even the bare possibility of produc-
ton from Quartz hill, Gilpin county,
section which has for long years
been identified with the production
in small quantities of high grade
pitchblende; nor of the circumstances
that the Kirk mine of this particular
territory made, within the last years.
shipment of several tons which netted
$23, 900 from French consumers.
On the other hand values are CIV
en- for 1000 pounds of Colorado car
notite, based on assay Of a few humid
red grams and on hypothetical go
U30S in "a large tonnage of carno-
tite ore" which values are from 1000
to 1850 too high.
submit. for Mr.. Forstall's consid-
Grafton and correction some factors
which are generally recognized in the
arithmetic of calculations OF these val
ues:
That 2a6O pounsiA OF uranium oxide
(U308) is equivalent to 1000 pounds
Of metallic uranium.
That in pitchblende, this would be
equal to yield of $50 milligrams of
metallic radium, or 500 milligrams
Of radtum bromide, making the pro-
portion of radium bromide to one uni
of 20 pounds of uranium oxide 424
milEigrams.
That refined radium bromide sold
by the Austrian government has been
paid fer at the rate of $50 per milli-
gram in small lots and $50 per milh-
gram in large lots.
That the cost of obtaining, or maxi
dng extraction from ore of l milli-
gram of radium bromide approximate
from SIS to $50 per milligram;
That an extraction of about 500
of the contained radium is about the
maximum possible.
AS for the rest of Mr.. Forstall's
pronouncements, there is the best
authority for findings contrary to
his in regard to relative radio activ-
ity and cost of working up the uran-
ium residues for the radium ele-
ment.
For instance, it can be maintain
ed that ores low in uranium content
are proportionately more expensive
to radium extraction than the high
err grade ores of the same metal Al
so 1t Is automatic that radioactivity
in pitchblende is directly proportion
al to uranium content. In this con-
nection 1T is indisputable that the
Gilpin county pitchblende is of su-
perior quality to that of Joachimst-
hal. Bohemia. supposedly be cause
of the associated rare earths, that
yield principally actimum.
OF the chemistry Of the process for
recovery of radium the article in re-
view does not impress since 1t fails
to state that the process In its es-
sentials is one OF repeated deduc-
tions through fractional crystalliza-
tions more than a Thousand times
repeated. Under the conditions an
extra fusion with alkaline carbonate
and separation OF heavy sulphides
are the merest bugaboos.
FORBES RICHARD.
May IA. 1918.