The Pirenópolis Gold Project, Goiás State, Brazil
A Greenfields Gold Exploration Project
Brazil remains one of the most underexplored gold jurisdictions in the world. Over 50% of the country remains geologically unmapped.
It is estimated that for every $1 spent on exploration in Canada only $0.005 equivalent has been spent in Brazil, yet Brazil has a similar area of potential geology, as Canada.
It was only beginning in 1988 that Brazil allowed 100% foreign ownership of mineral rights. This partially explains the exploration gap.
The town of Pirenópolis in the state of Goiás, Brazil was founded during the 1740’s Gold Rush which continued through to the late 1800’s. Much earlier than the gold rush in Australia and North America and pre-industrialization and mechanized mining methods.
In the late 1800’s alluvial gold mining shifted from the rivers to ferricrete paleo channels and benches. The ferricrete was hard and mined by diverting water flow. The local population started turning to cattle and cane agriculture for an economic base as gold production dwindled and conflicts arose around downstream water quality from mining operations.
Other than a few showings in the region, no primary source has been found to explain the gold. The region has never seen systematic modern exploration.
Pirenópolis Gold District
The headwaters of the Almas River had historic placer gold workings over 30km in distance as did other rivers in the region.
The mineral formations of the historic Lavras do Abade gold mine may be similar to that of the Kinross Paracatu mine. “Gold is in the shale rock matrix and is formed with small concentrations of crystal quartz, pyrite and oxides”¹. A visit is required to confirm. Secondary processes created higher grades at surface which were mined by open cut / hydraulic mining.
Pirenópolis is in the Mid to Neo Protorzoic Pan Brazilian Belt. The same belt and similar rocks host the giant Kinross Paracatu Gold Mine located 275km southeast.
The Pirenópolis gold project is classified as an orogenic type deposit with the distinct features of being stratiform hosted, friable calcareous phyllites with quartz veins and sericite alteration located on a regional structure.
2013 Costa, D. Historical Archaeology of Lavras Abade: An Environmental conflict in Nineteenth Century Brazil
Kinross Paracatu Gold Mine: >16m Oz Au
Psuedo-stratiform, hosted in carbonaceous phyllites.
The deposit formation model proposed for Paracatu suggests that gold and arsenopyrite were introduced concurrently during the regional deformation event.
Gold occurs as free gold and/or electrum
Large low-grade (0.4g/t Au). Upgradeable (simple scrubbing lifts the grade as the rocks are friable). Highly profitable.
The Pirenópolis Gold Project is in the same belt and age of rocks.
Little to no evidence of competitors exploring for these type of deposits.
2020 NI43-101 8.9Moz Au mined, 8Moz Au proven and probable reserves
Recent Sampling at the Pirenópolis Project
Pedra Anomaly Government Airborne Data
The Pedra anomaly has an interesting cross stratigraphic magnetic anomaly possibly representing a late intrusive.
A linear trend is interpreted as a district scale fault that could be a source for mineralization (black dash line).
Extensive thrust fault development is present at Paracatu.
Potassium (K) channel shows the Pedra anomaly occurs near a major structure.
Linear K channel trend paralleling the structure indicates potential alteration (black dash line).
Sericite minerals (K) are common at Paracatu likely due to extensive metamorphic alteration.
