Ann: Higher Grade Core Confirmed at Cortadera, page-39

I feel for CE because he seems to think he needs to "sell" the project when all shareholders want is information and education.

I'm quite interested in the comment he made to you about considering leaching the low grade sulphide. So I went back to the Productora PFS (now that I have found the entire document, although I've only skimmed it) because I recall they were planning an SX-EW plant to process heap leached copper ore. It is interesting because the Productora PFS only discusses leaching oxide ore. It says:

"The mine will also produce 3.3 Mtpa of oxide ore to be processed via a crushing/agglomeration/heap leach circuit coupled with an SX-EW plant producing up to10,000 tpa of copper cathode." That's a very low recovery rate for oxide ore and I note the PFS says the oxide ore grades 0.45%. But as I said earlier, grade doesn't really matter if you have to dig the stuff up anyway because it just sits in a heap and you process the copper in solution that comes out of it.

I haven't studied the mine plan for Productora but I find it interesting that the oxide mining and processing (cathode production) was spread out over the entire mine plan.






So leaching the low grade sulphate ore that otherwise might be considered waste is interesting. It is similar to what they do at Escondida as discussed by Noel Ong in the article I linked to earlier.

I'm thinking out aloud here because I am trying to learn more about all this. Any comments are welcome.