Mining giant Anglo American has come up against a brick wall in its efforts to convince the government of Namibia to lower the tax rate the diamond company they co-own is obligated to pay, Mining.com reports. Namibia's tax rate for diamond companies is 55%, but Anglo wants Namdeb, a 50-50 joint venture between itself and the Namibian government, to pay only 37.5%, the same rate as firms that mine resources other than diamonds.

Namibian diamond commissioner Kennedy Hamutenya ruled out of hand Anglo's suggestion, saying that the 55% tax rate was arrived at through careful deliberation, on account of the extraordinary value that diamonds carry on the global market. But Namdeb has a great deal of leverage with the government, since it is the second largest employer in the entire country, according to Mining.com. Namibia's diamond industry is reknown for its underwater diamond deposits, 80 million carats worth, almost two-thirds of the national total.