According to a BRWreport by Tim Treadgold, Magnetite is superior...

According to a BRWreport by Tim Treadgold, Magnetite is superior to Haematite "because it generates heat in the process of being converted to pellets and it produces less pollution, which is becoming an important factor in Chinese cities."

However, Haematite's advantage is that it does not need processing as it is 65% Fe (as opposed to magnetite's 35% average Fe) and can be directly shipped without having to upgrade or pelletise the ore up to 60%. It's a simpler material - just dig it up and ship it.

The article continues with many pros and cons. A good read. 15 March edition. "Magnetitue attraction".