Gold has long been west Africa’s dominant mineral, but iron ore is exciting more interest, says Rolake Akinola of Ecobank...The region is undeveloped and mining firms are busy exploring and discovering potential sites even as they develop new mines, he says...The Revenue Watch Institute, a New York-based lobby promoting better management of natural resources in the poor world, has helped Guinea’s government to draw up a new mining code, which requires the government to hold at least 15% of the equity in new mines. The code also sets a new tax regime and a higher threshold for foreign investors. This, says the institute’s Patrick Heller, could offer a model for other countries in the region. Guinea’s government is reviewing all existing concessions, as is Sierra Leone’s. Mali’s new government is expected to follow suit, and may renegotiate some contracts. Liberia is also drafting a new mining code. Ghana’s government has raised taxes on gold-mining companies, which say their operating costs will rise sharply. [refers to BHP Billiton, China Union, Moore Stephens & Aureus Mining]