Evening capital news. (Boise, Idaho) 1901-1927, 1919-03-16
MEso -THoRiUM AS A RADiuM
SUBSTITUTE.

| ingredients.
MEso-THoRiuM AS A RADluM
SUBSTITUTE.
An excellent substitute for radium,
for certain purposes. is mesothorium,
which is radio -active element found
| in monazite sand and other thorium
minerals. When first extracted it Is
not in satisfactory condition for the
manufacture of luminous paint; it
must be allowed to "ripen" for several
months, or even for a year. before 1t
can be used. During this time the
alpha radiation which is required for
luminous paint becomes sufficiently
strong. On the other hand, the beta
and gamma radiation of meso- thorium
grows rapidly, and it can be used for
medical purposes within few days
after preparation.
Radium has a long life, half of 1t
decaying in approximately 1900 years.
Meso- thorium, on the other hand, has
short life, five or six years being
its useful life for luminous paint pur-
poses. The price in the past has va
ried from 40 per cent to so per cent
of that Of radium, the comparison be-
ing on products of equal activity. For
medical purposes, therefore, 1t cannot
compete with radium as long as there
is plenty of the latter; for luminous
paint, when used on objects which
have short life, it is an excellent
| substitute for radium, and should be
the means of saving radium for medi
cal purposes. Undoubtedly it was
used, during the war. by the Ger
mans. Some of the first luminous
watch dials in this country probably
contained meso-th orium imported
from Europe.
Until recently no meso-thorium was
recovered in the United States, al
though large quantities of monazite
sand are treated annually for the
manufacture of incandescent gas man
ties, a condition that represented an
important mineral waste.
THoRlUM ORE.
The importations of thorium ore in
the form of monazite sand from Bra
I'll and India were practically normal
during 1918. The Brazilian. sand car
ries an average of per cent thorium
oxide, and is preferred by certain
manufacturers of thorium nitrate to
the Indian sand, which carries an
average of per cent thorium oxide.
Prior to 1914 the Indian deposits as
we'll as those of Brazil Were practically
controlled by German interests, and
nearly all the thorium nitrate was
| manufactured in Germany and Austria.
| Under the control of the German
| syndicate the price of the nitrate was
so regulated that French, English and
American indepSAdent manufacturers
were practically driven out of bust
ness. The German syndicate and large
| mantle factories in all Of the above
| named countries, which served to fur
Their strengthen its strangle hold on
/ the market. The war, however, put
an end to all these conditions and sew
eral independent manufacturers are
now supplying consumers with thoYium
| nitrate equal in quality to the best
Austrian or German nitrate. There
| was little or no fluctuation in price in
| 1918. During the first half the price
ranged from Sc to $3.50 per pound,
| with lower prices for yearly contracts.
Toward the end of the year, owing to
keen bidding among nitrate manufac-
turers for the 1919 requirements of the
mantle trade. the price dropped to
S. and $5,25 per pound. according to
| quantity. The worlds consumption of
thorlum ore is approximately 5000 tons
per annum. The consumption in all
countries OF incandescent mantles is
about 300,000.000. and the average
mantle contains the equivalent Of
about gram of thorium nitrate.
ZlRcONlUM.
| 1t had been known prior to our en-
try into the war that the Germans had
developed chromium Steel which was
claimed to be superior to vanadium,
chromium, molybdenum, tungsten or
nickel steel. The demand for light
| armor plate on tanks, aeroplanes. and
other equipment, compelled the gov
eminent to investigate the possibili-
ties of all steel-hardening elements
for such purposes. and it was ulti-
mately decided that chromium was the
best suited for the requirements Of
the war department Owing to the alb
sence of any authoritative technical
data of the production and uses of
ferro chromium, many difficulties We're
encountered, but ultimately through
the efforts of several large manufac-
turers Of ferro-ailoys, ferro-zir-
IL o. rAxxA nv nj