plumb, this one is out of my realm but i would think "inferred" resource might come into play. i dont know what the requirements are to judge a resource as "measured/indicated/inferred" but i would think the differance between the bulk sampling and drilling certainly "infers" the grade is better than the drill suggests.

i've noticed a funny trend recently though. it seems that measured/indicated/inferred carries a lot more weight than it used to when it comes to valuation.