Ann: Arrium Mining Quarterly Production Report, page-9

My first half calculations are.

September quarter average realised price $66/ton, average total cash cost $57.4/ton
66 - 57.4 = 8.6
8.6 * 2194000 (tons) = $18.8 million

December quarter average realised price $51/ton, average total cash cost $57.8/ton
51 - 57.8 = -6.8
-6.8 * 2126000 (tons) = -$14.4 million

First half
18.8 - 14.4 = $4.4 million gain, but the total cash costs are probably missing other costs because the September quarterly mentions targeted FY2016 average cash breakeven iron ore price ~US$47/dmt