Ann: Mineral Resource Upgrade, page-315

I love when people talk about things they obviously know nothing about...

"Soft Ore" lmao. The proper term is "Friability" which describes how easily a peace of rock will break in a crusher...
This has no bearing on the the processing plants overall design but does decrease the absorbed power.
Statements like this " lot less heavy machinery for the plant, so cheaper to build." tells me you have no idea of what a crushing circuit is.

For your information silica is the worst thing to find in your ore as this can reduce the manganese life from as high as months to as little as hours.

BTW your numbers are wrong, MGT has an all in cost of $54 per tonne at stage one (3mtpa). This cost is expected to drop to $40 per tonne by stage 2 (7mtpa). this reduction is mainly due to the inclusion of the rail slip line going the full 40kms to the processing plant.
So don't talk shit, MGT will do fine with a IO price of $100 USD per tonne.