Thanks Toph - I don't agree with Mark Hohnen's estimation of 500 million lbs just for Zones 1 + 2, quoted in the post you copied in for us. The data released so far doesn't indicate this, in my view.
Of course, Mark Hohnen may have access to other information that is not in the public domain. On the other hand, he has a reputation for exaggeration. You make your own mind up.
My own research is (at least in my own mind) far more robust in technique, and conservative in estimation. This is in the thread link I gave above, repeated here:
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