Ideas for a Quick Forensic Audit My original concern was with the quality of the data that PG used. The fact that PG's report was as devoid of detail as it was surprised me. As a result I've dropped my respect for PG's work.
However, my concern about the QA and related processes around the core were brough forward by what watchmeptz posted earlier about FC almost being kicked out but then deliverying some high grade core samples. Now couple that with the most excellent work prepared by steveaux (here is the link)
https://www.stockhouse.com/Bullboards/MessageDetail.aspx?p=0&m=31392454&l=0&r=0&s=BGM&t=LIST
and the need for a forensic audit becomes paramount just to confirm the whole cow mountain db is real. Specifically, steveaux noted the repeated 1 foot samples with identical grades 25.04 g/t tonne. Eye popping as steveaux noted not because of the grade but because 3 consecutive samples had identical values.
Now PG didn't do any checking of the cores, arguing that this was not possible when he faced 20 miles of core (my words but they do capture the spirit). Yet something doesn't look right.
So my question here to the experts, and I know many folks here have expertise with mining, is how could a cost effective verification of the core integrity be completed. My naive suggestion yesterday was to look a that 50 or even 100 feet of highest grade in the database and then do use a hand held scanner to get a grade estimate and present a table of results. So for the 100 feet of core, we could see a table that looks like
| HoleName |
AdCentreZ |
AU |
|
Scanner Result |
| CM11-102 |
4381.01 |
|
25.03 |
|
xx.xx |
|
| CM11-102 |
4380.15 |
|
25.03 |
|
yy.yy |
|
| CM11-102 |
4379.3 |
|
25.03 |
|
zz.zz |
|
Now add the other 97 highest 1 foot intercepts and lets see what the remaining half core shows on the hand held scanner. PG could easily have done this kind of verification if a few weeks of work and it would have added a huge amount of credibility to the report. And PG could even have built a nice graphic for 2guys showing the differences between Dr. Yin's excel spreadsheet AU column and the results of the hand held scan of the remaining half core out in the core shack. Yes there would be difference since the scanner is not near as accurate as the lab work but it should be indicative at least that is what the sales man for the hand held scanner tells me when ever I stop at his booth at a gold show.