112
THE MINERAL WEALTH OF BRAZIL
The
average during the 1920-9 period was 65,700 metric tons, that of the
1930-4 period 22,870 metric tons and the 1935-9 period, 1,040 metric
tons. In 1940, lhe imports totalled 67 metric tons 37 metric
tons of which was salt for industrial applications while 30 metric
tons was table salt. In the previous year, the former amounted to 95
metric tons and the latter 46 metric tons.
Pertinent
to these changes are the export and import prices of thd various types
of salt. The export price (FOB Brazil) in 1939 was 452 milreis per
metric ton while the import price (CIF Brazil) of the industrial salt
was= 366 milreis and that of table salt 1,038 milreis. In 1940, the
corresponding prices were 394 milreis, 593 milreis and 1,178 milreis.
Although
it is difficult to completely trace down the imports of prod-i nets
made from salt, it is of interest to point out two of some importance,
sodaii ash and caustic soda, the first because it comprises the largest
mineral salt in port and the latter because of the presence of one
plant in Brazil, the plans tos construct another and the large
annual demand in Brazil which continues to be. filled from overseas
sources in preference to its manufacture domestically des-] pite the
presence of abundant raw material. In 1940, the imports of soda ashf
amounted to 23,378 metric tons valued at 17,736 contos while that of
caustic^ soda amounted to 31,515 metric tons valued at 48,007 contos.
Domestic production of the latter amounts approximately to 1,500 tons
annually.
17. SEMI-PRECIOUS STONES
GENERAL SURVEY
The
use of semi-precious stones dates back to the days of Babylon, their
most important use at the time being for the manufacture of seals. Some
by their appearance were credited with having medicinal or magic
powers. To- day, practically the only use is for adornment and ornamentation.
The
characteristics of a gem are: beauty or splendor, durability
(de-pending principally on the hardness of the stone), rarity, fashion
(temporary and variable) and portability.
The
first of these qualities is brought out by cutting which may be
faceted, or by engraving, which may be in cameo, or carved or curvette.
The principal lapidary center for colored gems is Idar-Oberstein,
Germany. In Brazil colored stones are lapidated in Belo Horizonte
(Minas Gerais) and in Rio de Janeiro.
•
No satisfactory studies have been made on this subject, the interested
parties limiting themselves only to rudimentary and superficial
workings of the deposits. Gems are sometimes discovered accidentally in
the search for other useful minerals. During the past two centuries,
Brazil has produced a number of colored stones, principally beryls and
tourmalines, the production of which though not very significant, still
continues.
The
gem trade operated, until a few years ago, under complete free- dom and
for this reason, no statistical data as to turnover or production are
