Panantza – San Carlos
The Panantza and San Carlos Project concessions are located approximately 40 km north of the Mirador Project. Corriente was approximately halfway through the first phase of a planned 16000 metres of drilling on the Panantza project when these activities were suspended as part of the Mirador Project suspension order. The drilling was the start of a planned two-year program to complete a feasibility study at Panantza and San Carlos, designed to incorporate the Panantza and San Carlos concessions into a single large copper development opportunity.
Prior to 2006, Panantza was last drilled in late 2000. Results from this previous drilling at Panantza included hole PA013 with 299 metres of 0.76% copper, hole PA012 with 269 metres of 0.97% copper, and hole PA017 with 64 metres of 1.29% secondary copper at the surface followed by 383 metres of 0.75% copper.
In 2006, an additional 25 holes totalling 8400 metres were completed. Results include hole PA039 with 17 metres of 1.31% copper in a secondary copper horizon overlying 399 metres of 0.66% copper, hole PA041 with 443 metres of 0.60% copper, and hole PA052 with 276 metres of 0.77% copper.
Current Inferred resources at Panantza, which incorporate the 2006 drilling results into a block-model using updated geology models, and at a 0.4% copper cut-off, are approximately 463 million tonnes grading 0.66% copper, containing 6.7 billion pounds of copper. The 2006 drilling added close to a billion pounds of copper to the previous Panantza resource. Corriente will focus on converting most of this resource to Measured and Indicated categories during completion of the drill programme.
One objective of the 2006 Panantza drilling program was to define the southern edge of the Panantza mineralization. However, rather than delineate the edge of the Panantza deposit, the 2006 results indicate the Panantza mineralization extends farther south than previously recognized. The southernmost holes drilled, PA033 and PA034, were both terminated in copper mineralization averaging over 0.8% Cu at the hole bottoms, at approximately 330 metres and 342 metres deep respectively. The Panantza drill plan has now been expanded to complete additional holes to follow this mineralization to the south.
In addition, the deepest holes from this round of drilling (such as PA051) indicate that mineralization extends more than 200 metres deeper than previous drilling in the southwest portion of the deposit and mineralization remains open for further extension at depth. The deposit is also still open to the west.
San Carlos is believed to be the largest copper-molybdenum mineralized porphyry system in the Corriente Copper Belt, with dimensions of about 2000 metres x 2500 metres. The mineralization has been tested with 25 diamond drill holes at variable spacing, drilled by BHP Billiton in 1997 and 1998. The current block-model based, Inferred resource estimate, using at a 0.4% copper cut-off, is 600 million tonnes grading 0.59% copper, containing 7.7 billion pounds of copper. The next phase of drilling will attempt to expand the resources and convert the bulk of the Inferred resources to the Measured and Indicated categories.
A Preliminary Assessment Technical Report (the “Report”) for a 90,000 tonne per day combined Panantza-San Carlos copper mining operation was completed and made available on SEDAR in December 2007. Highlights from this study are:
- Base case Net Present Value ("NPV") after tax of US$676 Million and an Internal Rate of Return ("IRR") of 15.1% (using metal prices of US$1.50/lb Cu, US$7.50/oz Ag, US$550/oz Au and US$10.00/lb Mo, 8% discount rate, US$75/tonne and US $0.075/lb treatment and refining charges for Cu). Using US$2.00 copper, the after-tax NPV increases to US$1.718 Billion and the IRR increases to 24.1%.
- Average annual metal production over the first 10 years of approximately 418,000,000 lbs of copper, 22,800 oz gold, 1,110,000 oz silver and 2,800,000 lbs of molybdenum.
- The Report modeled a mine plan based on 678 million Inferred tonnes at a grade of 0.62% Cu, 0.05g/t Au, 1.3 g/t Ag and 0.008% Mo with estimated recoveries of 91% Cu, 30% Au (Panantza only), 70% Ag and 43% Mo.
- The cost to produce a pound of payable copper, net of other metal credits, and inclusive of marketing, smelting and transportation costs over the life of mine, is estimated to be US$0.73/lb.
- The Project would generate up to 2,000 jobs during the construction period and could create over five hundred direct and almost 4,000 indirect jobs during the estimated 20 year life.
- Total estimated value of taxes, profit sharing and expenditures within Ecuador over the twenty year Project life is approximately US$6 Billion.
The full Report can also be found here.
The Qualified Person for the resource estimate(s) quoted above is John Drobe, P.Geo, Chief Geologist.