ores have also been necessary
in order to raise the percentage of phosphorus and thus make the ores
suitable for the Thomas process; on the other hand the Spanish ores and
a small part of the Swedish material have been desired because of their
low phosphorus content, adapted to the acid Bessemer process and to the
manufacture of low-phosphorus pig. The Russian ores have largely been
smelted in that country.

The largest of the western European low-grade deposits is a geographic
and geologic unit spreading over parts of Lorraine, Luxemburg, and the
immediately adjacent Briey, Longwy, and Nancy districts of France. The
ores of this region are called "minette" ores. This unit produces about
a fourth of the world's iron ore. Low-grade deposits of a somewhat
similar nature in the Cleveland, Lincolnshire, and adjacent districts of
England form the main basis for the British industry. There is minor
production of iron ores in other parts of France and Germany, in
Austria-Hungary, and in North Africa (these last being important because
of their low phosphorus content).

Comparison of figures of consumption and production of iron ores
indicates that the United States, France, Russia, and Austria-Hungary
are self-supporting so far as quantity of materials is concerned.
Certain ores of special grades, and ores of other minerals of the
ferro-alloy group required in steel making, however, must be imported
from foreign sources; this matter has been discussed above. Great
Britain and Germany appear to be dependent on foreign sources, even
under pre-war conditions, for part of the material for their furnaces.
During the war there was considerable development of the low-grade
English ores, but this does not eliminate the necessity for importing
high-grade ores for mixture. Belgium produces a very small percentage of
her ore requirements and is practically dependent on the
Lorraine-Luxemburg field.

The principal effect of the war on iron ore production was the
occupation of the great French mining and smelting field by the Germans,
thereby depriving the French of their largest source of iron ore. Since
the war the situation has been reversed, France now possessing the
Lorraine field, which formerly supplied Germany with 70 per cent of its
iron ore. As the German industrial life is largely based on iron and
steel manufacture, the problem of ore supplies for Germany is now a
critical one. It has led to German activity in Chile and may