Chalco,
the 3 historical mines that were drilled and reported. Comstock, Shamrock and Falcon were all high grade underground Gold mines. They were only mined to like 15 and 20m like everything in that area because they got beat by the water. The average grade on those mines was around 50g/t gold. Ok it was underground and they had no dilution, but with drilling and free gold in the core and such high grades and I guess will be open cut they will have dilution. Also it is very well documented eg: Ballarat mining a few years back did not top cut the grade and included the nugget effect in the JORC estimates. We all know what happen there.
Mr Chalco i also assume you are aware that a top cut is put on resource calculation as is variography and smoothing to iron out the high grade (nugget effect) which can distort the calcs. If a drill hole has assays of 50g/t Au over two metres and two holes either side 25m away have 1m at 3g/t Au what would you suggest the average grade is Mr Chalco?? Cough cough. The program being used Vulcan or other will not give 1m either side of the holes with the 2m @ 50g/t. It will be determined “nugget effect” and discounted . Sure the program will determine what the top cut will be and that can also vary depending on the geology program used. If those three mines I mentioned above that mined gold at an average of 45g/t and in one case averaged 90 g/t Au and the drilling by Ausmex 10, 20, 35, 30 g/t Au will be lucky to show reporting I’ll bet you a case of XXXX that the grade after being shredded by the geology and resource program will be lucky to be 3g/t Au.
All of the low grades recorded from assays infiltrate the high grade and once tbd smoothing (go smooth the grades) and the variography allows computerised variations) depending on what parameters the geologist doing the calcs puts in decides on the final number.
So there is a topside cut. If there is no topside grade cutoff grade used in the calculations why do they use a bottom cutoff grade? There would be no point having a bottom cutoff without having a top cutoff. The computer does actually decide the top cutoff and the geo decides the bottom cutoff. That’s how it’s done, out in a simple form. To be honest if it’s over 1.5g/t Su and over 50,000 ounces I don’t really care how they got to the number.
Cheers BB
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