The calcs are basically correct, this thing should produce the 10c as calculated. A broker report I have on AVL indicates a NPV of around 70c discounted heavily for risk.
As production is bought in and political risks diminish price will rise. It is unlikely to trade on a high multiple but maybe 3 to 4 times current price seems reasonable until further reserves established.
Don't discount the risk- possibly worst country investment story on the worst continent, reliant on barges to carry production.
I hold quite a few and would buy more at 9c if money freed up.,