ly by increased importation. Imports
were mainly of regulus from Chinese and Japanese smelters of Chinese
antimony; but about a third was contained in ores, including most of the
production of Mexico which had formerly gone to England, and about 15
per cent of the Bolivian output. Antimony smelters were developed in the
United States to handle these ores.

At the close of hostilities there had accumulated in the United States
large surplus stocks of antimony and antimonial materials. With a very
dull market and low prices, domestic mines and smelters were obliged to
close down. The dependence of the United States on foreign sources of
antimony and the importance of the metal for war purposes led to some
agitation for a protective tariff--in addition to the present import
duty of 10 per cent on antimony metal--in order to encourage home
production (see pp. 365-366, 393-394).

In summary, the United States is almost entirely dependent upon outside
sources for its antimony, although there are inadequately known reserves
in this country which might be exploited if prices were maintained at a
high level. The future of United States smelters is problematical.
China, the world's chief source of antimony, at present dominates the
market in this country, largely due to the low cost of production and
favorable Japanese freight rates.

GEOLOGIC FEATURES

The antimony sulphide, stibnite, is the source of most of the world's
production of this metal. Antimony oxides, including senarmontite,
cervantite, and others, are formed near the surface, and in some of the
deposits of Mexico and Algeria they supply a large part of the values
recovered. Jamesonite, bournonite, and tetrahedrite (sulphantimonides of
lead and copper), when found in lead-silver deposits, are to some extent
a source of antimony in the form of antimonial lead.

Stibnite is found in a variety of associations and is present in small
quantities in many types of deposits. In the commercial antimony
deposits, it is in most cases accompanied by minor quantities of other
metallic sulphides--pyrite, cinnabar, sphalerite, galena, arsenopyrite,
etc.--in a gangue of quartz and sometimes calcite. Many of the deposits
contain recoverable amounts of gold and silver.

The deposits of the Hunan Province of southern China occur as seams,
pockets, and bunches of stibnite ore in gently undulating beds of
faulted and fissured dolomitic limestone. In the vicinity of the most
impo