My enquiries make me wonder if it's too early to judge the two...

My enquiries make me wonder if it's too early to judge the two holes as duds. The pre-collar, I gather, advances the hole some of the way using fast drilling methods, whereupon diamond drilling takes over for the deeper stage. Barrick apparently haven't advised the precollar depth, but if it were say 200m for argument's sake, then there would still be 200m of depth remaining in one hole and 400m in the other in which to strike it lucky.

I understand also that the targets for these holes were indeed deep, so maybe the lack of mineralisation in the pre-collar was only to be expected.

Don't rely on this information. Do your own research.