Chromite ore is graded by its chromic oxide (Cr2O3) content, and its price is reported in trade journals on a gross-weight basis (U.S. dollars per metric ton, gross weight). Commercially traded chromite ore grades range from 35% to 55% Cr2O3. Suppose, for example, that a particular chromite ore is graded at 42% to 45% and priced at $100 per metric ton. It contains 42% to 45% chromic oxide and costs $100 per ton, gross weight.

To calculate the cost of the chromium contained in this material, remember that chromic oxide is 68.42% chromium. Consequently, 1 ton of this material then contains between 0.287 and 0.308 ton of chromium yielding
a unit value of between $325 and $348 per ton of chromium.