erer received no compensation for his trouble, and was left to
find his way back as best he could.
The richest mines, in the opinion of King, are those of the
Sierra da Frio, which, since their opening in 1727, have
yielded more than two tons of diamonds. Burton, who visited
the mines of Minas Geraes, says, since their opening in the
seventeenth century, to 1850, they have yielded nearly six
million carats, valued at more than fifty million dollars, besides
those surreptitiously secured by the miners. In a single year
the Portuguese imported from these mines between eleven
hundred and twelve hundred ounces of diamonds. The
government, to protect its assumed right to all the gems
found in the territory, had recourse to the unjust act of driving
away the inhabitants living on the banks of the rivers where
they were found, and many of the poor fugitives perished
from want, before the edict for their restoration to their possessions was promulgated, in 1805.
The Bahia mines, embracing a territory eighty miles long
and forty wide, which were discovered by a slave, were opened
about forty years ago, and to the year 1880 had yielded nearly
ten million carats of diamonds. The production was so great
that their value was reduced at least one half, but at present
the yield is considerably less. The stones are found in the
cascalho taken from the beds of streams, and sent to Rio, at
great trouble and expense, for exportation to foreign markets.
The South American diamonds are known in commerce as the
Diamantina and the Cincora ; the former are considered the best.
The Brazilian diamonds were formerly thought to be
different in some of their essential qualities from the Indian,
but it is now conceded that they are alike with the exception
of a slight difference in specific gravity, the oriental being a
little heavier.
