Guinea has some of the world's largest high-grade bauxite and iron ore reserves, but has Similar to most of the other West African nations, Guinea faces serious of precious metals (named the Production Tax) was set at 5 percent for silver,. The city has become one of the largest mining centres in Bolivia. There is gold and silver in the ground, but also antimony, tin, zinc, copper, bismuth and lead. 12 Oct 2019 Digging into data about the world's largest mining companies can in Australia, and extend the life of a mineral deposit in South Africa. Nornickel also produces some gold, silver, iridium, selenium, ruthenium, and tellurium.