Channel Samples Under estimate Bulk ( milled ) grades… ....in a coarse gold environment , and grade control elevates drilled grades.
The link below is an excellent exposition of sampling theory as applied to estimating gold grades in a coarse grain environment such as QWN.
Gold grades have 4 presentations ....modelled Drill core assays , Channel samples , bulk samples and Grade
control.
Examples are provided for several gold mines in the link below.
Its a long detailed read , not for those who prefer to read summaries
Once again, both bulk and channel gold grades substantively under estimated head grades upon entering the mill to be processed.....channel grades by a factor of 2
Further, grade control can substantively elevate grades extrapolated from core assays.
Based on KT channel results, I decided to test the posit that Channel grades can substantively under estimate modelled grades from core assays.
Recall that the average grade of KT combined phase samples was 2 ounces ( 62 grams ) per ton.
This was just for those assay meters that contained gold....11% .
That is, 89% of the meters sampled were dusters ( quite within normal statistical distribution of coarse gold ) .
Accounting for these dusters, it can be computed that the average grade of KT Channel samples was
6.8 grams per ton .
From the Keats Main Mett study, the modelled grade ( what was estimated as resource ounces and grades ) is 15 grams per ton
So, as in other studies of coarse gold like QWN, we see that channel grades can substantively under estimate modelled grades detived by representative bulk mining.
In short, test mining of KT down to a modest depth of 25 meters should provide very robust cash flows
as provisionally estimated..
FWIW
GLTA
https://www.researchgate.net/profile/Simon-Dominy/publication/233634363_General_considerations_of_sampling_and_assaying_in_a_coarse_gold_environment/links/594a37e90f7e9b0d8526835f/General-considerations-of-sampling-and-assaying-in-a-coarse-gold-environment.pdf?origin=publication_detail&_tp=eyJjb250ZXh0Ijp7ImZpcnN0UGFnZSI6Il9kaXJlY3QiLCJwYWdlIjoicHVibGljYXRpb25Eb3dubG9hZCIsInByZXZpb3VzUGFnZSI6Il9kaXJlY3QifX0