Tapajos Regional Exploration
The Tapajos Region of Brazil covers an area of 100,000 km2 (approximately equivalent to the area of Belgium). Within this Region, Serabi has concessions totalling approximately 97,000 hectares including the Jardim do Ouro tenements.
The presence of gold in Tapajós Mineral Province has been reported as early as 1747 from the Colonial Portuguese era. Gold production in the Tapajós commenced in the mid 20th century via garimpeiros reaching a peak in the 1970’s and 1980’s with estimated production of between 15 to 30 tonnes per year, from over 500,000 garimpeiros. Production has since declined. However there remain in the order of 2,000 to 5,000 garimpeiros producing in the order of five tonnes of gold per year from the region. Total historical production from the Tapajós is estimated at between 15 to 30 million ounces but accurate reports do not exist.
The garimpeiros typically worked alluvial and colluvial gold sources up stream until they came upon the residual source. Generally, the garimpeiros worked the residual mineralized saprolite profile containing free primary and secondary gold. In circumstances where extremely high grade was encountered in fresh rock, the garimpeiros sunk shafts and mined the vein underground by gallery development. The mining method employed traditionally was by hand and hydraulic mining in the saprolite, using basic gravity separation and occasionally mercury amalgamation. In the high grade vein material extracted from fresh rock or deeper open casts, the material was crushed and then gravity separated and/or mercury amalgamated.