Perseus Mining Ltd (ASX:PRU, TSX:PRU, OTC:PMNXF) has boosted mineral resources and ore reserves at the Yaouré Gold Mine in Côte d’Ivoire through a maiden estimate for the underground orebody beneath the existing CMA open pit.
Indicated mineral resources amount to 3.7 million tonnes at 4.48 g/t for 537,000 ounces of gold and inferred resources are estimated at 3.7 million tonnes at 4.1 g/t containing 488,000 ounces.
Importantly for mine planning, maiden underground probable ore reserves estimated to date total 2.2 million tonnes grading 3.58 g/t gold and containing 259,000 ounces of gold.
CMA measured & indicated mineral resources.
Adds to Yaouré profile
The estimate paves the way for the initial stages of mining of the CMA orebody by underground methods, adding to the life and value of the deposit and the Yaouré project.
This has been proven by a pre-feasibility study (PFS) on the drilled-out portion of the CMA deposit about 200 metres down dip, which demonstrates the economic and technical viability of underground mining.
CMA inferred mineral resources.
Perseus says that the addition of the CMA underground deposit to the Yaouré Mine has the potential to extend the Life of Mine and increase the annual ounce production profile by substituting low-grade open pit feed with higher-grade underground reserves.
CMA probable ore reserves.
Perseus’ managing director and CEO Jeff Quartermaine said: “Having attained the goal of producing gold at a rate of 500,000 ounces per year across our three gold mines, we are now working to maintain, and where possible, exceed that level of production over the next decade and beyond.”
Potential for more
And there is strong potential to further increase the underground resources and reserves with positive results from ongoing drilling.
The first hole in a program to test a target generated from a 2020 3D seismic survey has intersected CMA mineralisation significantly further down dip than any previously drilled hole, intersecting 6 metres at 2.11 g/t, including 2 metres at 5.5 g/t.
"These latest drill results from Yaouré give us further confidence in the high-grade gold contained beneath the CMA open pit and the results of a pre-feasibility study and maiden ore reserve for the first portion of CMA Underground Project are encouraging,” Quartermaine added.
“Very profitable extension”
"This initial stage of the development will carry the bulk of the development costs of the underground operation, and as further resources and reserves are delineated by the drilling programs currently underway on the site, the average AISC should be reduced turning the CMA underground into a very profitable extension of the already profitable open pit operation.
"We look forward to progressing Perseus’s first underground mining development which is also likely to be the first large-scale underground mine operating in Côte d’Ivoire.”
Lifts overall resources
The maiden underground resource for CMA along with strong exploration drilling results has also helped Perseus boost overall resources and replenish ore reserves for its West African projects.
Perseus Mining mineral resources.
Total measured and indicated mineral resources at June 30, 2022, are estimated to be 132.9 million tonnes grading 1.19 g/t gold, containing 5.079 million ounces of gold, compared with the estimate of June 30, 2021, of 130 million tonnes grading 1.18 g/t for 4,942 million ounces.
Perseus Mining ore reserve.
The updated resources and reserves ensure the long-term sustainability of the group’s production profile.
As well as the new estimate at CMA, drilling at the Nkosuo Project of the Edikan Gold Mine during the year resulted in a maiden resource and an ore reserve of 10.0 million tonnes at 1.04 g/t gold, containing 332,000 ounces of gold.
Nkosuo is a substantial addition to the Edikan Gold Mine, extending the life of the mine by 18-24 months to FY2027.
And then there is Block 14
As well as the three West African producing assets, Perseus has a 70% interest in the Block 14 Project in northern Sudan, near the border with Egypt, obtained when the company acquired Orca Gold Inc (TSX-V:ORG) earlier this year.
Block 14 is a large and scalable resource with an indicated resource of 79.9 million tonnes at 1.3 g/t for 3.3 million ounces and an inferred resource of 18.5 million tonnes at 1.2 g/t for 700,000 ounces. It has a probable reserve estimate of 79.9 million tonnes grading 1.1 g/t for 2.9 million ounces.