Evening star., 1932-10-30

A LUMINUM the most abundant of all metals
in the earths crust. is nevertheless SO
closely controlled in production that the price
Of the metal is held more or less uniform and
overproduction is held to minimum. 1t is esti-
mated that six countries, the United States
Canada, Germany France, Switzerland and
Norway, produce about 88 per cent Of all the
aluminium processed. The United States leads
in the manufacturing of the metal and France
leads in the mining Of bauxite, from which
aluminium is taken. Hungary, Dutch Guiana,
Italy British Guiana and Yugoslavia are the
other principal producers Of bauxte.
According to the Bureau of Mines only two
elements. oxygen and silicon, the latter the ele-
ment which enters into all the various types OF
sand exceed aluminium in quantity in the earth.
The metal is found largely in two types of de-
post the most widespread of which is clay
In various parts of the world cays running as
high as 20 to 35 per cent in aluminium are found.
but these while theoretically sources of supply
Of the metal, are not commercially feasible in
competition with bauxite, which is found III
extensive deposits.
Bauxite is not a substance for which any
formula can be written, fer it is largely mix
ture of mineral substances which is the residuum
of rock from which silica and other substances
have been leached out by natural processes.
Bauxte runs as high so to 60 per cent in
aluminium, and therefore makes readily avail
able percentage of the metal which keeps its
production at fairly low cost.
The general term of laterite is applied to rock
which has been leached, and if it is sufficiently
free of silica and aluminium predominates in the
metallic contents remaining, the laterite Is
termed bauxite. Because bauxite Is compare
lively in relating to other sources of alumni
mum, yet presen. in concentrations which more
than supply the worlds needs, bauxite has be-
come the almost exclusive source of the re-
fined metal.
Approximately three fourths Of the bauxite
produced goes into the refining Of the metal
the rest being devoted to such purposes as
cement manufacture, refractory materials.
abrasives and filtration material for refining OIL
The production of aluminium in the metallic
form is a two-step process. the first being the
production alumina or the oxide of aluminium
from bauxite and then the production of the
metal itself from the alumina It requires four
tons of bauxite to yield two tons of alumna
and two tons of alumina to produce one ton
of aluminium.
Many new uses for aluminium have developed
in recent years. and relatively high prices for
tin and copper have encouraged intensive re-
search to effect substitution Of aluminium for
those metals Aluminium Is now employed ex-
tensively wherever Hghtness, durability and
strength are important. The size Of structural
elements made Of aluminium and its alloys is
increasing rapidly, due to more extended use
of these metals in the superstructures of build
ings. In the building of railroad coaches, air.
planes and automobiles and for other purposes
The first bauxite produced in the United
States was obtained in 1889 from deposits in
the North Georgia field, and in 1891 bauxite was
first produced from the Alabama deposits. Prac-
tically all the bauxite mined in the United
States until 1899 came from these two States
In 1896 the first shipments were made from
Arkansas deposits, but it was not until 1900 that
their influence was felt. In 1907 bauxite from
the Tennessee deposits was first shipped. The
total production of bauxite recorded from 1889
to 1890, inclusive, Is 7.830399 long tons.
As the largest consumers Of bauxite in the
United States are also the chief producers, and