"The target was for copper mineralisation with zinc and gold...

"The target was for copper mineralisation with zinc and gold credits in either a structural or VHMS setting. The results to hand are extremely positive and the core is now being prepared for assay"

The extremely positive comment relates to the target and implies to me that they got a pretty high grade copper reading, but they can't report grades except from lab assay. However if they return results of 2% or more copper, over decent widths, then the stand alone project value should be $10-$20m, or would be if it belonged to a junior copper explorer.
The value of the silica project, if it can be shown to support decent quantities of DSO high grade silica, should also be multiples of $10m. I did note though, the lack of reference to off take agreements.

They are preparing the way for JV's to take over the exploration cost in exchange for a share of the project or for a sale or spin off of the assets they hold, so that they can focus on the aluminium division. This is the obvious choice as its annual EBIT potential far outweighs the mineral side, but the mineral holdings still have the potential to realise many millions of dollars, one way or the other and it would be stupid of the company to ignore that.