Separate physical mass yield from actual fine-gold yield. This prevents a common analytical mistake: assuming that product mass alone tells you how much gold was recovered.
Processing changes concentration. A product may weigh much less than the feed while containing most of the gold. Conversely, a large product can still represent poor gold recovery. Fine-gold yield is therefore the more relevant metal-recovery metric.
When mass yield and fine-gold yield differ substantially, the process has changed the concentration of gold and other materials. That is often exactly what a beneficiation or refining process is designed to do.
The product's gross mass as a percentage of feed mass.
Recovered fine gold divided by contained feed gold.
Yes, if gold becomes substantially more concentrated in the product.