You're talking about the gross value of metals sold by some point in the future, assuming the deposit poves to be economic.  The present worth of something like this to a discovery company has to be disounted by so many things it, it's very hard to guess what value it may have in present terms.

How many partners have to be brought in to have extracted that possible gross value?

What would be left to them if they don't sell out fully by that time? 

If they sell out early for a guaranteed royaly interest, how may years will it take for that cash flow to begin, and how may few millions will they get up front for that, if anything.

If it helps, I've seen large discoveries in Africa sell for 1 to 10 percent (most around 2) of anticipated gross value.  ...depends of size and richness - the larger, the less value per share.  Having said this, what I recall is from the early 90s, a very much hotter time for miners, and at a time when financings were easy to comeby (from bankers and sercuities firms who are not in this market any longer).

If LBSR soon has a discovery at ESB, I would put a 2 percent valuation on it, or 1 percent if they have already sold a 50 percent interest the that time.  However, the longer they hold their interest, the more valuable it can become as exploration continues, even if further diluted by attiditional partnership interests over time.

But, I would think LBSR would want to leverage as much cash out of ESB as soon as possible so as to get on with work at Hay Mountain, and to build interest there and to surrounding existing and possible new claims. 

My point is, ESB will give new life to this company.  Beyond that, it's value will be hard to estimate.  I will look to at least a doubling or tripling of the share price if Ironwood is removed from National Monument status.  Then at least a double or triple if LBSR gets a partner, and another double or triple at the start of drilling.  Discovery could make the stock a 5-10 bagger from there. 

What this means is that the gross future value of the depost, should it prove economic to develope, is almost irrelevent

All in my opinion, of course.