It will mine the stuff in Mexico, paying its expenses in either pesos or $US. It will sell the stuff for $US. The net profit will be distributed back to shareholders, being converted into $A.
If anything matters, it's the $US/$A exchange rate.
Now, if you were mining the stuff in Australia (therefore paying expenses in Australia), then the $A price of gold/silver is highly relevant.
So, get it right: it's the exchange rate, not the $A pos that matters.
BSG Price at posting:
0.0¢ Sentiment: ST Sell Disclosure: Held