The Barre daily times. (Barre, Vt.) 1897-1959, 1919-12-01
RADIUM MINERALS
ARE NEAR GRANITE
Radium Has Been Isolated Only Once
or Twice and Few Persons
Have Seen 1t.

AnsI SCSA H.
Radium minerals are generally found
in connection with granite masses
that is, in places where granite forms
at least part of the rock of the country.
Most of the original radium minerals,
such as uraninate. samarskite, and
brannerite are black and have a shiny
fracture and high specific gravity,
These minerals are rarely found in
commercial valuable quantities. Pitch
blende, which has the same compost
ton as uraninate and the same general
appearance except that it shows no
crystal form, occurs in veins 1t has
been found in only a few places lin
Bohemia, southern Saxony, Cornwall
and Gilpin county, Colo. When these
original minerals break down through
weathering other radium minerals are
formed from them, such as autunite,
torbernite, carnotite and tyuyamunite.
The Most Abundant Radium Minerals.
Carnotite and tyuyamunite are the
most abundant Of these minerals and
now furnish the bulk OF the world 5
radium They cannot be told apart by
the eye, for both are of bright canary
yellow color and are powdery, finely
crystalline, or, rarely, claylike in tex
ture. Carnotite is a hydrous potas-
sum uranium vanadate. Tyuyamunite
is similar in composition but contains
lime instead Of potash. The greatest
known deposits Of these two minerals
are in southwestern Colorado and
southeastern Utah, where both are as
ISOLATED with fossil wood and other
vegetation in friable, porous, fine
grained sandstone Small quantities
of carnotite have been produced near
DIARY, South Australia. The only 9TH
er deposits that yield tyuyamunite in
notable quantity are those Of Tyua-
Muyun, in the Andiyan district, Ferg-
hama government, central Asiatic Rus
STA Russian Turkestanl, where tyuya-
munite occurs with rich copper ores in
a pipe in limestone.
Tests of the Minerals.
A drop of strong hydroehloric acid
| on either earnotite or tyuyamunite
gives IL at once a rich reddish brown
color, and the addition Of drop of
water Immediately changes the color
to yellowish green. The reddish brown
color shows the presence of vanadium,
and the yelIowish green color the pres
ence of uranium, for it vanadium alone
were present the color would be clear
green or blush green. Iron, however,
may interfere with the tests, producing
color that covers OF masks the others
Surer tests may be made either with
an electroseope or with Photographic
plate. If a piece of rsdium bearing
ore is placed on plate holder contain
ing a sensitized plate with only the
cover Of the plate holder between the
specimen and the sensitive film of the
plate, the plate will be eight struck
in from "a hours to or days, the
length of time consumed depending on
the richness of the specimen. Speci-
mems should never be placed on the
plate itself, because the pressure of
the specimen will give an effect that
Stimulates light striking. This test may
be made with other uranium minerals
to which the ecid test given would not
be applicable,
Commercial Form Of Radium.
Radium is a metal and is described
as having a white metallic luster. 1t
has been isolated only once or twice,
and few persons have seen it. 1t is
ordinarily obtained from its ores in
the form Of hydrous sulphate, chloride,
or bromide, and it is in the form of
these salts that it is usually sold and
used These are all white or nearly
white substances, whose appearance is
no more remarkable than that of com
mon salt OF baking powder Radium
radium salts and radium minerals are
not generally luminescent. Tubes CON
tanning radium salts glow because they
include impurities which the radiations
from the radium cause to give light.
Radium is found in nature in guam
titles so exceedingly small that it Is
never visible even when the material
is examined w.sh a microscope. Ra-
dunn orc ordinarily carries only a
small fraction of grain of radium to
the ton, and radium will never be found
in large masses, because it is formed
| by the decay of uranium, a process
that is wonderfully slow; and radium
itself decays and changes to other ele-
ments so rapidly that 1t does not ac-
p11mulatn naturally In yisihla massps