RE: b warrants.. thoughts? Since you ask... here's my thoughts.
Base on that the company did let the two other warrant series expire. I doubt it very much that the company apply to extend the B warrants. As you said, considering the lack of activity of MLR in investing it is also doubtful that the stock price reach $2.50 by June 2013.
On another upbeat note, looks like MLR’s gloriosus major shareholder Vladimir Iorich (or Pala) has once again invested at great lose (he is very good at that) with ML. Just a month ago he increased his holding in ML to about 19%. Since then ML reported a cut to its 2012 output forecast on lower ore grade and that problem financing the Mexico mine project and ML share price is as its lowest. Same with NCU.
Here’s an interesting point of view from Peter Campbell from Jennings Capital Investment.
"Jennings' Campbell noted that Pala often becomes an activist shareholder in companies in which it takes large stakes."
"And I think that when Pala gets involved with a company and shakes things up, it ends up hurting the companies at the end." (from below link)
https://www.miningweekly.com/article/mercator-rises-after-pala-geologic-say-wont-back-board-2011-03-23
So, all this lead me to consider the B warrants that I hold dead. Only a miracle will bring some life to them. That miracle might be for someone to buy Vladimir out of MLR.
Goodluck
D.