Blue-
I think that drilling on top of the mountain is about as certain to be successful as drilling in the Sinker. The veins are not deep and horizontal, but tilted or vertical. They actually can be seen and traced on the surface, in some cases for a mile or more. That's how the gold and silver on WEM was discovered in the first place, long before drilling was used to find veins. I'm sure RS and especially RW have done a thorough job of examining the surface showings of the veins and evaluating where to drill, certainly more work than has been done since mining essentially stopped in the 1800s. The Sinker of course would be a preferable area to mine from, since it can be worked year round. But don't discount the surface intersections of the veins- that's where all the gold and silver has come from so far.