It's Indonesia here - most likely cyanide will be used and government regulation for environment would not be as strict as here. Lots of political drama there as well. Gold at Cadia Valley is mined at as low as 0.6g/t so this is quite rich.
While it might sound quite rich, considering the cost of opening a new mine is easily more than millions of dollars, you really need to have that much gold / copper to justify the capital expenditure, overhead, labour cost, mobilization, demobilization, hedging against volatible metal prices and so forth. Not to forget the investors' expectation of profitability. Wait, you might have unions wanting more - it never ends.
Get into the mining industry and you'll have a better idea.
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