RE: RE: RE: re: thoughts on the 43-101This was discussed heavily on the CBS private board (everyone startedposting there because this forum became overrun with spammer-types).This is my understanding (don't base any decisions on this, people!check it out yourselves!):
Basically the designed pit is beyond the scope of the NI43-101resourceestimate and should not have been included therein. The publishedwaste:ore ratio is based on very conservative assumptions that skew itbigtime. If you calculate the contained tonnage in a 700m deep cone (45degree walls, 1.4km diameter) with the top 200 m cutoff using 3tons/cubic metre you get the approximate total pit tonnage used in theestimate. If you bank the walls to 50 degrees from horizontal thetonnage decreased by 35%. To 55 degrees is a decrease of about 45%.
Anyways, the assumed slope of the walls impacts the ratiosignificantly. I don't have access to the spreadsheet I made but Ithink the numbers I came out with doing a 51 degree slope (fromhorizontal) and including the 0.03% Mo was something like 3.5:1. I onlyplugged in the numbers to see how much the ratio could be altered givendecently realistic scenarios (what I judged). Obviously the cost ofkeeping the pit walls stable increases along with steepness, anddepending on their composition, and that ought to be considered in an amore thorough analysis.
My main point is to use careful judgment and avoid placing too muchimportance on the pit design/ratios in the NI report. I don't claim toknow much other than things I've read from what I consider reliablesources. This is simply the conclusion I made given the current stateof knowledge of the resource.