[26 
ECONOMIC GEOLOGY 
supply but uses nearly half. The Chinese output may be 
reduced by political disturbances; but as a civil war in 
China usually has a less disturbing effect on business than a 
general election in some countries, the Chinese mines will 
probably maintain their output unless there be a fall in 
price. 
Tue DistrRIBUTION AND FORMATION OF ORES—Owing to the 
varied chemical combinations of antimony it has a wide range 
in distribution, from deposition as a primary constituent in 
deep-seated lodes, to secondary segregations and deposits 
near the surface. The chief commercial mineral stibnite, 
Sb,S,, containing 71-4 per cent. of antimony, is either 
primary or secondary. Many sulphides of antimony with 
lead, copper, and silver are also primary. The chief secondary 
minerals of commercial value are the oxides ; they are some- 
times associated with native antimony that has been formed 
by the reduction of sulphides or oxides. Stibnite is a deep- 
seated primary mineral in the tin-tungsten lodes of Bolivia, 
in gold-quartz in Bendigo in Victoria, in the Phoenix Mine at 
2300 feet in Rhodesia, and in the silver-lead veins of the 
Harz Mountains and of British Columbia. That stibnite 
has also been deposited as one of the later sulphides is shown 
by its occurrence in cross-course veins, as in Cornwall. The 
main supplies of antimony come from shallow secondary de- 
posits of stibnite, of which the distribution is similar to that 
of mercury. 
The characteristic occurrence of stibnite is in large nodular 
or kidney-shaped masses often with a radial structure. 
They reach the size of 3000 Ib. in sandstone in southern 
Utah; 2300 Ib. in granite in Bohemia ; 1200 Ib. in the upper 
part of the Cornish copper lodes; and 500 Ib. in Arkansas ; 
large masses also occur in California, and at Whroo in Vic- 
toria; an incomplete stage of segregation is represented by 
the irregular bunches of ore in New South Wales. 
The prolific antimony deposits in China are due to secon- 
dary concentrations near the surface. The most important 
mine is at Hsi-K'uang Shan in Hunan (Tegengren, Geol. 
Surv. China, Bull. iii, 1021, pp. 1-25). The field consists of 
Silurian, Devonian, and Carboniferous rocks, which have been 
compressed into folds and traversed by innumerable cross- 
iractures. The sandstones have been shattered and the