JP Morgan Target, page-10

THese guys are analogous to any company in a counter cyclical downturn of its sale product , but capable of still making a profit , once the prices swing to the upside only the profitable companies will have survived so supply is reduced which has to cause the sale product to increase in value ,
And the sale product supply will be constrained in supply as it is magnetite not the more ubiquitous hematite, with several magnetite producers making huge losses ie GBG , they wont survive .
Rather basic economics for JP Morgan to get wrong in addition to not accounting for GRRs book value.