Yandera gets more feasible

MARENGO Mining has more than doubled the measured copper resources of its vast Yandera copper-molybdenum-gold project in Papua New Guinea through a resource update which underpins the ongoing definitive feasibility study.
Yandera gets more feasible Yandera gets more feasible Yandera gets more feasible Yandera gets more feasible Yandera gets more feasible

Last year the measured resources totalled 113 million tonnes at 0.57% copper equivalent while the upgrade undertaken by a different consultancy, Ravensgate, established 248Mt at 0.43% copper based on a cut-off grade of 0.25%.

The update was based on assay results from 465 diamond core drillholes compared to 345 in the resource estimate last year.

Unlike the calculations last year, Ravensgate does not use copper equivalent grades for its JORC-compliant reporting.

Based on a copper cut-off grade of 0.25%, measured and indicated copper resources totalled 361Mt at 0.43% copper while inferred copper resources were estimated to be 218Mt at 0.37% copper.

"The resource update supports the previously stated goal of achieving a minimum operating life of at least twenty years," Marengo managing director Les Emery said.

"The measured resource category has increased by over 100 per cent and substantial additional resources have been upgraded from the inferred to indicated category."

He said more drilling was continuing at the Yandera Central deposit, nearby exploration targets and for infill tasks.

"Furthermore, areas of higher grade (more than 0.5 per cent copper) have been identified that, with the advantage of topography, can potentially be targeted for the initial years of possible production," Emery said.

While additional inventories for the silver and rhenium found in the project area were yet to be calculated, the updated resource established 532 measured and indicated resources of molybdenum at 119 parts per million molybdenum - about two-thirds of which was in the measured category.

Measured and indicated gold resources came in at 199Mt at 0.17 grams per tonne gold with nearly 78% in the measured category.

As part of the ongoing FS work, Marengo said it would go forward with a combined rock waste dump and tailings storage facility.

Managing tailings disposal is one of the trickiest issues in PNG because of very high rainfall.

The resource estimate was previously expected in the March quarter while the DFS was flagged for completion midyear.

The project is 95km southwest of the provincial capital of Madang and is initially expected to produce 100,000 tonnes of contained copper plus 15,000t of contained molybdenum a year over a 20-year life but the new estimate proves there is scope for expansion.

Marengo previously estimated mining approvals could be made in the September quarter of 2013, construction was tipped to start 24 months later and the project was targeting production in 2016.

Marengo wholly owns Yandera but in 2010 struck a non-binding deal with China Nonferrous Industry's Foreign Engineering and Construction Co over possible financing, construction and offtake aspects of the project.

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