I feel You are correct in a round about way . Apart from grade ,...

I feel You are correct in a round about way .
Apart from grade , You need scale as far as the value of ore per vertical meter of the ore body being at least several times the value of the cost of development per vertical meter
in Au terms one normally considers 1000 ounces per vertical meter as the bench mark for a viable mine

next need to look at the total Life of mine quantity of copper , as that determines the economics of the payback on a plant, this does have the advantage of being related to satellite ore bodies in improving economics of the plat , but satellite ore bodies will not improve the inherent economics of the main Antler ore body for actual mining

I did own this briefly, but found as you state in simpler terms this lacked scale , after selling , I asked the MD in person a few questions and was surprised at his answers which I found quite hard to consider possible (to put it mildly) .