carbonados approximates the total in practically all years and thus furnishe an index as to the trends in the industry.
Annual
exports of precious stones in the 1920-9 decade averaged 15,945 contos
while in the 1930-4 quinquennium, there was a drastic decline to 1,669
contos and in the 1935-9 five-year period, they increased again to
aveiage 16,351 contos. In the first mentioned period, carbonado
exports were larger than that of diamonds accounting for 40% of the
total whiie that of diamonds amounted to 31%. Other gemstones
represented 29% of the total. In the fol-lowing five-year period,
carbonados accounted for a larger percentage share amounting to 55%
while the diamonds represented 41%. It is only in the 1935-9 period
that there is a distinct domination of the trade by diamonds (94% of
the total) due largely to the extraordinarily large shipments of 1939.
Car-bonados in this period represented but 2% of the total. It may be
noted that in 1940, the total exports of this nature consisted of
diamonds and carbonados only, that of the former being 81,403 contos
while the latter amounted to 1,180 contos.
From
the above trends, to all appearances, the importance of carbo-nados has
declined to new levels despite the perceptible increase in the last few
years. One significant reason for this change is evident in the growing
use of borts and the smaller diamonds in the place of carbonados.
According to the Minerals Yearbook, 1940, smaller stones are
said to be sounder and harder than the larger. There is the additional
discovery of a new cast-setting metal of be-ryllium-copper which
permits the use of small diamonds and which will no doubt greatly
affect the trade in carbonados.
Imports
of precious stones vary but slightly although there is a notice able
decline in the five years from 1930 to 1935 in which they averaged 840
contos as compared to the 1,400 contos of the previous decade and 1,600
contos ; for the quinquennium 1935-9. In 1940, the imports amounted to
499 contos.
DIAMONDS
The
uses of diamonds are- divided between the industrial applications and
that for ornament. However with the fears of contingencies arising from
the "unexpected", diamonds have lately served another purpose, such as
that as an investment for capital.
The
discovery of diamonds in Brazil dates back to 1729 and their
exploitation from that date in the state of Minas Gerais became one of
the most important activities of Colonial Brazil.
This
country soon became the world's principal producer of diamonds. The
stones acquired an excellent reputation for their unequalled clearness
and brilliancy and competed on even terms with the diamonds of
Hyderabad, India whose mines at Golconda served as a standard for
Brazil. It may be said that the world-wide popularization of this gem
was due to its discovery in Brazil;
