With the official rate for bolivars so far from the real market rates (2.15 official vs 7 on the black market) it's pretty difficult to calculate costs or income with any precision because the final selling price in real tems depends on the access Vz allows to the "official" exchange rate more than any other factor.

Hugo has seemed to realise that this widening difference between the official and black market rates has provided him with even more power over all enterprises that need to buy or sell on international markets. Overuse of this power can, and will, eventually cause the country to collapse economically, but apparently he has been blinded by the short term power which has been created by his own economic mismanagement.

Some costs like labour and fuel will be in bolivars and may become cheaper in US dollar terms short term, but all imported materials like machinery, spares, chemicals, explosives etc. will become dearer in the same terms.

In effect this requirement to sell 70% of gold produced locally (which will undoubtedly be in bolivars at the official rate) means that the government can dictate the profitability of any gold miner simply by restricting or approving access to US dollars at the official rate. They don't have to control anything else! If they completely deny the miner any access to the official rate to buy dollars, every mine becomes a losing proposition. If they allow 100% access of all sales proceeds to the official rate then it becomes a huge success (for the miner).

When you consider that every company (not only gold miners) has to make application to exchange any money from bolivars to any external currency it means that Hugo can dictate the success or failure of any operation on a whim at any time. I am sure that favoured companies and connected people will get the nod, but any falling out with Hugo could result in immediate bankruptcy simply by denying or delaying all applications to exchange bolivars at the official rate.

And we all know that Vz officials are past masters at deny and delay in regards to permits.