I would feel a bit sleazy calling this a "new find" as the mine has been producing for decades, but the quality that this pocket produced has not been recovered in years.  Part of that is due to the mine being privatized-- whereas blasting used to be in intervals of 5 meters, technological advances mean that the blasts now destroy up to 15 meters at the time.  Also, the new owners have been VERY strict about allowing specimens out.  

This was one piece from a medium sized lot that I purchased.  As the person who sold them to me put it-- the group this belonged to was selected from "many tons" of specimens, and judging from what I usually see, I am inclined to believe him.  It is never difficult to buy pyrite in Peru, but finding good pieces is another story entirely-- there are usually only a couple per trip, though on that last trip, I got lucky.