162
MINERALS YEARBOOK, 1941

 Although official data are lackmg, the serious need for zmc for military
and civilian use indicates that world production and consumption of this-
metal were greater in 1941 than ever before. Some of the details by countries,
where such mfoi~mation is available, are discussed m the followmg pages Owmg
to the serious lack of data for 1940 and 1941., the table showing world smelter
production has been omitted.
REVIEW BY COUNTRIES

 Argentina —Production of zmc concentrates m Argentma m 1941 amounted
to 66,010 metric tons containing about 36,300 tons of zinc, only slightly
below the 1940 total of 66,384 tons containing approximately 37,000 tons
of zinc.. The Aguilar mine of the St. Joseph Lead Co. in the Province of
Jujoy is still virtually the only producer. This and other smaller. mines
supply concentrates for the Puerto Vilelas smelter. During 1940 a large percentage
of . the output of concentrates accumulated as stocks as the result of difficulty
m disposmg of them In June 1941 the United States, through the Metals Reserve
Co, purchased the greater part of such stocks on hand Reportedly this purchase
amounted to 100,000 long tons of concentrates containing 42,500 long tons
of recoverable zinc.
 A'ustralia.—Base-metal production statistics for Australia for 1941
are i~ot available. A prominent feature in development work at the various
zinc properties is the use of diamond drilling. Late in 1941 diamond drilling
at New Broken Hill gave evidence of a reversal of pitch of the present ore
body, which, if true, means that the mam body to the south will be shallower.
This would have an important bearing on future mining practice. Operations
at Broken Hill during 1941 contmued m the usual efficient manner, at North
Broken Hill the mam feature of the mmmg operations has been the contmued
success attendmg extraction of ore from lode pillars, as 23 8 percent of
the ore mined in the North section dithng the last operating p3riod was won
from this source. Ore reserves were, estimated at 5,232,000 long tons as
of June 30, 1941. Broken Hill South, Ltd., introduced a hydraulic system
of ' stope ifiling Lower-grade crude ore treated at this property during
1941 was offset by improved metallurgy resulting in the following recoveries:
Lead, 96.1 percent; silver, 92~2 percent; and zinc, 89.1 percent. The latest
available figures for the Zinc Corporation, Ltd., indicate ore reserves of
about 3,650,000 long tons.
 TheBroken Hifi Associated Smelters at Port Pine are reported to be conducting
research as to the feasibility of recovering zinc from accumulated blast-furnace
slag containing 15.78 percent zinc and a minor amount of lead. Mt. Isa Mines,
Ltd., Queensland, continued to make a steady output of zinc concentrates
during 1941. Estimated suffide ore reserves, as of June 30, 1941, have been
reported to total 8,775,300 tons averaging 8.65 percent zinc.
 Boliv'ia.—Mine production of zinc (content in ore) in Bolivia amounted
to only 6,065 metric tons in 1941 compared with 12,197 tons in 1940. Bolivian
output of zinc ore and concentrates is cornparatively small, and no apparent
reserve stocks are carried.
 Brazil.—The zinc-bearing zone of the Iporanga district, São
Paulo, is the most important in Brazil. Reserves of sphalerite and calamine
ore, containing 31 to 36 percent zinc and estimated as amounting to
-30,000 metric tons, have been reported near the Apiai lead-silver