What you do, right, is you grind it up to a powder. Wet it. Then...

What you do, right, is you grind it up to a powder. Wet it. Then you pass it through a bed of bentonite mud with an SG of 3. The quartz, SG 2.67, floats. The hematite, SG 4, sinks. You then create a hematite con which is going 66% Fe, and everyones happy.

Bingo, the ore can have 44% silica and its no disadvantage. Well, aside from the whole 'grinding' bit. Which is a little bit of a pain in the ring, but no more than magnetite and if its friable itabirite similar to that in the quadrilatero ferrifero, and heavily weathered, no pain at all.

Mountains out of mole hills.

I'm having the same argument with nincumpoops over on the AGO thread.