The New International Encyclopædia/Bauxite
BAUXITE,  (from Baux; see below).
The most important ore of aluminum, a hydrate
having the composition AlO3HO, though most
occurrences contain also some silica, iron oxide,
and titanium. The ore occurs in rounded grains,
in pisolitic or claylike masses. The grains usually
show a concentric structure and a variable
color from white to yellow, brown, or red. It is
named from its occurrence at Baux, in France,
but it is also known from Styria and Carinthia,
in Austria, and from Antrim, in Ireland.
In the United States it occurs in a belt about 60

miles long, extending from northwestern Georgia
into northeastern Alabama, and also in
Arkansas, near Little Rock. The foreign deposits
result from the chemical alteration of igneous
rocks; the American deposits are thought to be
hot-spring formations. Those of Alabama and
Georgia are basin-shaped, and are limited
vertically to points between 900 and 950 feet above
sea-level. The composition of good-grade American
ore is approximately as follows: Alumina,
57 to 62 per cent.; ferric oxide, under 1 per
cent.; silica, 2.5 to 3 per cent.; titanic acid,
3 to 4 per cent.; water (combined), 20 to 30 per
cent.; moisture, retained mechanically, 2 to 4
per cent. While bauxite serves chiefly as an
ore of aluminum., it is also employed in the
manufacture of alum, and for lining basic
converters and Siemens-Martin furnaces in the
manufacture of steel. Consult: Hayes, "Bauxite,"
Sixteenth Annual Report United States
Geological Survey, Part 3 {Washington, 1895);
Mineral Industry, Vol. II. (New York, 1893);
Branner, “The Bauxite Deposits of Arkansas,”
Journal of Geology, Vol. V. (Chicago, 1897).
See, also, the articles on  and .