brr interview, page-2

Re grind size, I think this is how it works

A smaller grind size allows you to extract more FE ore from the dirt leading to a higher % of concentrate.

However a smaller grind size is more expensive to obtain when processing ore.

The economics of processing is a balance of the grind size and the % ore extracted. Each ore has its own characteristics.

Depending on the ore it may be more economic to have a larger grind size but lose some of the FE or incur the extra cost of a smaller grind to obtain more FE.

This is its importance as they will need to know this in order to maximise the efficiency of their benefication process and helps them work out the potential costs and rewards. So fairly important when working out the feasability of a mine