Calculate the true weighted average purity of mixed gold lots. Larger lots receive proportionally more influence, unlike a simple average of percentages.
This is the correct mass-weighted approach when combining materials with different purities.
A 10 g lot at 99% and a 1,000 g lot at 50% should not receive equal influence. The larger batch contains much more material and therefore dominates the weighted result.
Yes, as long as the weights and purity inputs are comparable.
No. It is a calculated batch average, not an assay certificate.