Cabral Gold Inc (TSX-V:CBR) has hailed testwork on the gold-in-oxide material at its MG target within its Cuiú Cuiú gold project in Brazil, which shows the deposit could be processed via the heap-leach method.
The extensive oxide blanket at MG was not recognized until 2021 and was generally considered waste in earlier resource estimates. Adopting heap-leach processing could result in significantly lower capital investment and costs.
Cabral said it would now advance to a preliminary economic analysis (PEA) of the gold-in-oxide blanket as soon as possible.
Alan Carter, Cabral's CEO, told investors in a statement that the column leach test results were "very encouraging".
READ: Cabral Gold says drilling results from Cuiú Cuiú gold district further indicate high-grade corridor of mineralization
"The overall leach recovery of 82% is excellent and higher than most heap leach gold mines that are currently in operation," Carter said.
"Furthermore, the results indicate that the composite sample used for the column leach tests may contain more gold and be higher grade than the assays from the composite sample indicate. The possible reason for this is that coarse gold particles may occur within the oxide material," he added.
The tests showed that gold recoveries based on the calculated gold content of the bulk sample were 82% after 70 days. Recoveries after 15 days were 70% and recoveries after 30 days were 78%.
Leached gold recoveries were 0.974 grams per tonne (g/t), which was "significantly" higher than the average assayed head grade of 0.896 g/t gold from head screen analysis of the composite bulk sample before the leach test.
Cabral highlighted that the column-leach recoveries compared "very favorably" with G Mining's metallurgical recoveries of 71% from the saprolite oxide material at the open pit Tocantinzinho deposit, also in Para state, Brazil, which account for just 3% of the planned overall Tocantinzinho mill feed.
The column-leach recoveries from Cuiú Cuiú also compare very well with other heap-leach gold mines around the world, noted the company.
Cabral Gold is a junior explorer with a primary focus on gold properties in Brazil. It has a 100% interest in the Cuiú Cuiú gold district located in the Tapajós Region, within the state of Pará in northern Brazil.
Two gold deposits have so far been defined at Cuiú Cuiú and contain 43-101 compliant indicated resources of 5.9 million tonnes (Mt) at 0.90 g/t for 200,000 ounces and inferred resources of 19.5Mt at 1.24 g/t for 800,000 ounces.
Contact the author at giles@proactiveinvestors.com