The overall quarter's realisation price was $57.14/t and...

The overall quarter's realisation price was $57.14/t and $52.94/t for the Dec half. All-in costs of $46/t FOB means a profit of $11.14/t (=$8.7M profit for the Q. This is in line with previous cash of $507-$22(divvy)-$18(KI expenditure+$9 profit =~$477M with rounding).

The increase in costs to $47 - 52/wmt is a concern, but I suspect there is some lumpy sustaining capital expenditure coming through. If that's the case, this isn't a cause for concern.

Note that the US$21/dmt is the low grade fines price only; the above realised price is for all product. On first glance it appears that MGX looses money on the low grade fines. But from the point of view that this material is a by product of lump production, and possibly also constitutes "waste" rock, the US$21/dmt realised price should be viewed as "salvage" value (ie, you can mine "high grade" waste and attendant low grade fines at $46/t and get nothing, or receive a low US21/t.) Again, this is not a concern.