Ann: SMS to give TNG Process and Product Guarantee, page-54

https://www.*.com.au/iron-ore-price-china-manufacturing-pmi-2018-12

Article linked
58% fines (there is a cost to mill) $40.59
62% $65.95
65% $82.30

TIVAN process cost $1.37 to improve by 1% - let's round up to $2
$25 extra per tonne from 58%-62%
4% improvement cost using TIVAN $8 net $17
From 58% to 65% $42 more
7% improvement using TIVAN $14 cost Net $28 more.
But I'm going out on a limb here & suggesting it will be nowhere near this high.

I've just read an old Balla Balla presentation - all of their grades - Ti, V, Fe are significantly higher than Mt Peake. Their Fe grade of 45% to get to 65% with TIVAN I'd suggest they'd only be looking if the cost is more like 50c-$1 Per %

Oh & there is this....higher grade IO is part of this