Adjusting drill angle corrects grade but under estimates OzThe logic is simple.
For QWN, the arbitrary cut off is 1 gram per ton which, applied to raw unadjusted assay grades , eliminates too many ounces as the actual cutoff is above 1 Gram per ton .
That is, as applied to my estimated ounces for Iceberg Trench , actual drill angle adjusted grade...as you have estimated..is 25,5 grams rather than 31 grams.
This of course means that , Prorata , the unadjusted cutoff , would be 1 gram X 31/ 25.5 = 1.2 grams .
That is , adjusting for drill angle over estimates grades and therefore, as calculated, ounces but also over estimates cutoff grade and therefore , as calculated , under estimates ounces .
The trade off is not actually proportional but roughly so.
That is, my estimated ounces below Iceberg Trench is not unduly biassed by drill angle adjustment ..