More important to size is the grade. Operating costs are...

More important to size is the grade. Operating costs are incredibly high for low grade deposits. You can have $28billion worth of gold in the ground its not worth much if it costs $30billion to extract it.

As a rough guide... I own a company who expect operating cost of $450-490/oz the grade is over 6grams per tonne.

Even with gold prices as they are some companies mining grades of 1g/t are struggling when things go wrong with operations. Naturally there is also greater risk with lower grade deposits that they may not be profitable at all if the price of gold goes down significantly (though I don't see this happening).

Worry about grades not size.

I am always skeptical of grades below 1 gram/tonne.
Think about the bigger picture...not revenue...but profit.