What you need to know before visting Brazil's historic mining towns
In 1785, another deposit was discovered 100 miles west of the first. Throughout the eighteenth century, interest in diamond mining exploded, attracting prospectors from great distances and increasing the demand for slave labor. Between 1700 and 1800, approximately three million carats were extracted from Minas Gerais. The largest diamond ever found in Brazil was a 254-carat stone, named Star of the South, discovered in 1853 in a Minas Gerais city today called Estrela do Sul.
Diamond deposits were also found in the states of Mato Grosso, Amazonas and Rondonia.
In 1842, a deposit was discovered in the Bahian interior at the Rio Mucuge, that today is part of Chapada Diamantina National Park. As a result of diamond discoveries in the area, the towns of Lencois, Andarai, Mucuge and Palmeiras became known as the Circuit of Diamonds. Visitors on Brazil tours will be glad to know that Chapada Diamantina National Park’s Waterfall of Mosquitoes derives its name, not from the insect, but from the water’s resemblance to the tiny diamonds called mosquitoes.
Most of the diamonds were alluvial deposits, though rare black diamonds were discovered in the Serra da Sincora area of Bahia. Using slave labor, diamond-bearing sand and gravel was retrieved from river beds by divers and chipped away from hillsides. Because the valuable commodity was generally covered with a material that was difficult to remove, the extraction process in alluvial mining was arduous and dangerous. The material was then rinsed again and again before the rock could be examined and diamonds culled from the alluvium by hand. Slaves did much of this tedious work as well. To eliminate theft, slaves were rewarded for their honesty with small gifts. If a large enough diamond was found, a slave could win his or her freedom.
Recognizing the value inherent in the product, the Portuguese government imposed strict regulations on the diamond industry as well as a hefty tax. To be allowed to mine, prospectors were required to make an upfront payment in gold equal to 20% of the estimated value of the deposit, called the Royal Fifth tax. Societies were formed to pool prospector resources.
Towns boomed. Towns folded. From 1725 to 1860, Brazil remained a leading diamond producer until major deposits were discovered elsewhere. Today, Brazil is one of about a dozen countries with a diamond industry, carried out mostly by multi-national corporations, but by prospectors as well, in the same regions where diamonds were originally found.