Study Estimates $5.2 Billion Cost for Tampakan Copper-Gold Project

Exploration drilling activity at the Tampakan copper-gold project in the Philippines, described by Sagittarius Mines,
the project developer, as the largest undeveloped Cu-Au deposit in southeast Asia. (Photo courtesy of Xstrata).
Sagittarius Mines, the operating company developing the Tampakan copper-gold project on Mindanao island in the Philippines, has completed an extended prefeasibility study that outlines a project costing $5.2 billion to develop into a mine producing 340,000 mt/y of copper and 350,000 oz/y of gold over 20 years of operation. Sagittarius is owned 62.5% by Xstrata Copper, 34.2% by Indophil Resources and 3.3% by the Alsons Corp. The study includes a potential schedule for development, commissioning, and first production in early 2016. Mill recovery rates are estimated at 83% to 90% for copper and 60% to 80% for gold in a copper concentrate grading 34% to 37% copper.

The Tampakan project is located 65 km north of General Santos City on the boundaries of three provinces: South Cotabato, Sultan Kudarat and Davao Del Sur. The deposit is in the province of South Cotabato. The latest Tampakan mineral resource estimate stands at 2.2 billion mt containing 12.8 million mt of copper and 15.2 million oz of gold at a 0.3% copper cut-off grade.

High-sulphidation style copper-gold mineralization at Tampakan is broadly associated with and central to a flat-lying tabular body of pervasive silica and silicaclay alteration developed within a districtscale cap of advanced-argillic and argillic hydrothermal alteration that extends over an area of 90 km2 within the volcanic complex.

At an approximate 0.3% copper contour, the Tampakan deposit comprises a flat-lying to gently dipping, tabular body of mineralization extending over an area of 2 km by 7 km and ranging in thickness from 200- to 400-m. Deposit geology has been developed from a systematic program of diamond drilling that currently comprises 157 completed holes (59,220 m) with most holes ending in lower grade (0.2- 0.4% Cu) porphyry-copper style mineralization at downhole depths of 350- to 500- m. Drilling density generally varies from 80 x 80 m over selected higher-grade parts of the deposit to 160 x 160 m elsewhere.

Preliminary “order-of-magnitude” financial modeling of the options indicated that a large open pit with certain assumptions in respect of the marketability provided the most viable economic outcome. Tampakan ore, according to Indophil, responds well to simple conventional flotation processing. Sagittarius is planning to begin the public consultation phase for the Tampakan project’s Environmental and Social Impact Assessment process later this year.

As featured in Womp 2009 Vol 05 -