MINING IN AFRICA SPECIAL — InterStar in production at Tambao

The Tambao manganese deposit in Burkina Faso contains proven reserves of more than 15 million tonnes (including about 600,000 tonnes of minable talus, or float, ores) grading 51.45% manganese, says InterStar Mining Group (CDN).

The Toronto-based company, which initiated production in early 1994 and by mid-1994 was producing about 5,000 tonnes per month, says the float material assays about 53% manganese. The deposit — an exposed outcrop rising more than 200 metres from the generally flat regional terrain — is said to require only minimal provisions for dilution and mining losses. “About 50% of Tambao’s reserves grade over 53% manganese, ranking this orebody as the largest, highest-grade, undeveloped deposit now known,” says the company in its prepared notes.

The company will selectively mine the high-grade talus material and the higher-grade ores from benches cut into the exposed ore faces; these high-grade reserves are considered adequate for the market for the foreseeable future.

The crushed and screened material is trucked to Kaya, from where it travels by rail to the export port of Abidjan in Ivory Coast.

InterStar says manganese ranks third or fourth in annual world consumption, after iron and aluminum and on par with copper.

An economic advantage of mining manganese is that the raw ore generally requires only crushing and screening (and sometimes washing); there are no costs for grinding, processing, concentration, smelting or refining. The major consumers of manganese ore are the steelmaking and ferroalloy industries.

InterStar is negotiating a joint venture to develop long-term manganese markets in the iron, steel and alloy industries of China, Japan, Korea, Taiwan, Indonesia and elsewhere in the Pacific Rim.