TradeVerify coltanIt is a black and opaque metallic mineral composed of the mineralescolumbita and tantalite. the denomination coresponde to the contraction of the name of two well names .lacolumita mienerales (COL) niobia with ymaganeso iron oxide. Fe, Mn Nb 2) 06 and tantalite (TAN) The interest of the exploitation of coltan is based primarily on being able to extract the value of coltan tatalita depend on the rate-typically 20% to 40% and the percentage of tantalum oxide in the tantalum content may be 10% and 60%