In 2014, Brazil Minerals was in urgent need of cash to seize the remaining % ownership of the MDB property as well as 50% ownership of all RST properties before they were usurped by another party. To make it possible in a timely manner, the company resorted to toxic financing which was simply the fastest option at the time. The move was essential for LONG-TERM viability of BMIX. Then, while the company was in its weakest first quarter of 2015 (historically, due to Brazilian weather), the toxic lenders proceeded to do what they do best -- dump their holdings all at once, without the regard for PPS. The simple concept of supply and demand came into play. The toxic debt resulted in too many shares supplied too fast, and there was not enough demand at the time to absorb all of the shares at higher PPS.
The good news here is that the variable-rate debt of Brazil Minerals is almost gone, and it will be very shortly that BMIX will rise back to its fair PPS levels due to no longer being encumbered by the onslaught of converted shares. I expect a blockbuster PR about the end of toxic debt to skyrocket the stock's price shortly.