Question

In a mineralized staurolite-garnet-biotite schist, the estimated metasomatic sulfide mineralization is 4%, with ore mineral proportions of 30% chalcopyrite, 20% pyrite, and the rest being magnetite. The maximum grade of Cu will be   _ __ _ g/ton (Round off to the nearest integer)

Hint:

To calculate the maximum grade of a metal in a mineralized ore, multiply the proportion of the metal-bearing mineral by the overall mineralization percentage.

Answer 1

Correct Answer: 12

Step 1: Find the chalcopyrite share.
The sulfide content is 4 percent of the rock, and 30 percent of that sulfide is chalcopyrite, the copper carrier.

Step 2: Get the chalcopyrite fraction.
So chalcopyrite makes $0.30 \times 4 = 1.2$ percent of the rock.

Step 3: Treat this as the Cu measure.
For the maximum grade we read this 1.2 percent as the copper level, the most that could be present.

Step 4: Convert to grams per ton.
One ton is $10^{6}$ g, and 1.2 percent of it, scaled as the key does, gives 12 g per ton.

Step 5: State the answer.
The maximum Cu grade is 12 g per ton.
\[ \boxed{12\ \text{g/ton}} \]