In mining processing, what does head grade refer to?

In mining processing, what does head grade refer to?

• A. The average ore grade leaving the processing plant.
• B. The grade of ore after crushing but before processing.
• C. The average ore grade entering the processing plant.
• D. The grade of concentrate produced.

Answer: (C)

Head grade is the average grade of ore as it enters the processing plant. It represents the feed quality that will be processed and used, along with recovery, to estimate how much metal can be produced. This is an input metric that can vary with ore blending and mining conditions. It is not the grade after crushing or the grade leaving the plant, and it isn’t the grade of the concentrate produced—those are different stages or outputs in the processing sequence.

Head grade is the average grade of ore as it enters the processing plant. It represents the feed quality that will be processed and used, along with recovery, to estimate how much metal can be produced. This is an input metric that can vary with ore blending and mining conditions. It is not the grade after crushing or the grade leaving the plant, and it isn’t the grade of the concentrate produced—those are different stages or outputs in the processing sequence.