Vancouver, British Columbia--(Newsfile Corp. - July 31, 2024) - Cabral Gold Inc. (TSXV: CBR) (OTC Pink: CBGZF) ("Cabral" or the "Company") is pleased to provide results from three additional column-leach metallurgical tests on three samples of gold-bearing oxide material from the MG gold deposit within the Cuiú Cuiú gold district in northern Brazil.
Highlights are as follows:
- Gold recoveries from three samples from the MG gold deposit (i) blanket soil, colluvium and sediments, (ii) low-grade saprolite material and (iii) higher grade saprolite material from the MG gold deposit ranged from 92 - 93% after 68 to 112 days of column leaching
- The results for all three samples were very consistent and confirm that heap-leach processing is highly viable at the MG gold deposit and that heap leaching of the oxide material is likely the preferred option for processing
- These results are a notable improvement on previous column leach tests conducted on a composite sample of blanket and saprolite material from MG, which returned 82% gold recoveries after 60 days
Alan Carter, Cabral's President and CEO commented, "These column leach test results are very encouraging and confirm that that the gold-in-oxide material at the MG gold deposit at Cuiú Cuiú is amenable to heap-leach processing. The leach recoveries of 92% to 93% are excellent and significantly better than previous test work which revealed an 82% recovery. They are also significantly higher than most heap leach gold mines that are currently in operation. These results should allow us to positively adjust our projected gold recoveries which form part of the ongoing prefeasibility study. These gold recoveries are particularly significant given the recent excellent drill results we are seeing from the Machichie Main and Machichie NE targets which are located only 500m and 650m north of the MG gold deposit, and indicate significant potential for additions of gold-in-oxide material in close proximity to MG."
Column Leach tests
As part of the ongoing prefeasibility study on the gold-in-oxide material at Cuiú Cuiú, Cabral collected mineralized material from the MG gold deposit and shipped three composite samples to Kappes, Cassiday & Associates ("KCA") lab in Reno, Nevada to conduct heap-leach metallurgical testing. The samples were collected from diamond drill core drilled at a number of locations over the extent of the near-surface MG oxide resource.
Three composite samples were created representing the two principal material types in the resource: one composite in the colluvial blanket zone (consisting of soils and sediments) and two composites representing the saprolite zone (consisting of weathered mineralized intrusive material). The MG blanket composite was designed to represent material near the average grade of the zone, whereas the saprolite composites were designed to represent high-grade and low-grade examples of mineralized material within that zone.
KCA completed a comprehensive series of metallurgical tests on the samples including extensive assaying, compaction and permeability tests, bottle roll tests, agglomeration tests, and column leach tests.
Samples were crushed to minus 50mm size then agglomerated with addition of 20 kg/MT of cement. Leach tests were conducted in columns eight feet (244cm) tall by eight inches (20cm) in diameter.
Samples were subjected to leaching with a dilute cyanide solution over periods lasting from 68 to 112 days (Table 1, Figures 1 and 2). Gold recoveries in all three samples ranged from 92% to 93% with +70% of gold recovered in under 20 days. Sodium cyanide consumption was low ranging from 0.31 kg/t to 0.48 kg/t NaCN.
KCA Test No | Description | Grade calc. head g/t Au | Extracted g/t Au | Av. Tails g/t Au | Extracted % Au | Days of Leach | Consumption NaCN kg/t |
93719 | MG Blanket | 0.440 | 0.411 | 0.029 | 93% | 68 | 0.48 |
93722 | MG saprolite High grade | 1.568 | 1.449 | 0.119 | 92% | 112 | 0.37 |
93725 | MG saprolite Low grade | 0.580 | 0.539 | 0.041 | 93% | 68 | 0.31 |
Table 1. Summary of column leach test results for MG samples. g/t = grammes per tonne gold, kg/t + kilogrammes per tonne
Figure 1. Cumulative gold extraction vs time for three MG gold composites
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/3900/218360_d1c5e075443c8be9_002full.jpg
Figure 2. Cumulative gold extraction vs Solution to Ore for three MG gold composites
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/3900/218360_d1c5e075443c8be9_003full.jpg
Results of all three samples demonstrate excellent recoveries in the order of 90 to 120 days. These column tests further confirm that heap-leach processing of the oxide blanket and saprolite material is viable at Cuiú Cuiú and is likely the best option for processing. The adoption of heap-leach processing could result in significantly lower initial capital investment and processing costs than other processing routes. In general, the adoption of heap-leach processing has the potential to significantly improve the economics for a potential future mining operation developed at Cuiú Cuiú.
The gold recoveries reported here (92-93%) are significantly better than the previous column leach test conducted on composite oxide material from the MG gold deposit which resulted in a gold recovery of 82% after 70 days (see press release dated 21st June 2022). This may be because the previous single MG composite consisted of material from both the colluvial blanket and the underlying saprolite material. Cyanide consumption rates were also lower (0.31 - 0.48 kg/t) than the previous test (0.51 kg/t), as was the amount of cement used previously (23.96 kg/t) versus the amount used in the most recent tests (20 kg/t).
Results are currently pending on three column leach tests that are being conducted on material from the Central gold deposit and are expected during Q3 2024.
About Cabral Gold Inc.
The Company is a junior resource company engaged in the identification, exploration and development of mineral properties, with a primary focus on gold properties located in Brazil. The Company has a 100% interest in the Cuiú Cuiú gold district located in the Tapajós Region, within the state of Pará in northern Brazil. Two main gold deposits have so far been defined at the Cuiú Cuiú project which contains National Instrument 43-101 compliant Indicated resources of 21.6Mt @ 0.87 g/t gold (604,000 oz) and Inferred resources of 19.8Mt @ 0.84 g/t gold (534,500 oz) as per the 43-101 technical report dated October 12, 2022.
The Tapajós Gold Province is the site of the largest gold rush in Brazil's history which according to the ANM (Agência Nacional de Mineração or National Mining Agency of Brazil) produced an estimated 30 to 50 million ounces of placer gold between 1978 and 1995. Cuiú Cuiú was the largest area of placer workings in the Tapajós and produced an estimated 2Moz of placer gold historically.
FOR FURTHER INFORMATION PLEASE CONTACT:
"Alan Carter"
President and Chief Executive Officer
Cabral Gold Inc.
Tel: 604.676.5660
Technical information included in this release was supervised and approved by Brian Arkell, B.S. Geology and M.S. Economic Geology, SME (Registered Member), AusIMM (Fellow) and SEG (Fellow), Cabral Gold's Vice President, Exploration and Technical Services, and a Qualified Person under NI 43-101.
Neither the TSX Venture Exchange nor its Regulation Services Provider (as such term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
Forward-looking Statements
This news release contains certain forward-looking information and forward-looking statements within the meaning of applicable securities legislation (collectively "forward-looking statements"). The use of the words "will", "expected" and similar expressions are intended to identify forward-looking statements. These statements involve known and unknown risks, uncertainties and other factors that may cause actual results or events to differ materially from those anticipated in such forward-looking statements. Such forward-looking statements should not be unduly relied upon. The Company believes the expectations reflected in those forward-looking statements are reasonable, but no assurance can be given that these expectations will prove to be correct.
To view the source version of this press release, please visit https://www.newsfilecorp.com/release/218360