:: Talvivaara to Test Bio-Heap Leaching

Talvivaara Projekti Oy (TPO) plans to conduct a large-scale bio-heap leaching trial at the Talvivaara polymetallic sulphide deposit in Finland during 2005. Bench-scale testwork has indicated recoveries of 90% for nickel and zinc, and 60% for copper and cobalt, over a leaching period of 550 days.

Talvivaara, which was previously investigated by Outokumpu, contains a JORC-compliant measured and indicated resource of 280 Mt averaging 0.27% nickel, 0.14% copper, 0.024% cobalt and 0.55% zinc that would be suited to open-pit mining. TPO is currently completing an updated prefeasibility study of the project, and envisages an operation producing 30 kt of nickel, 60 kt zinc, and 10 kt copper per annum. The cost of mine development is estimated at 250-350 million euros.