Although chalcopyrite crystals themselves are nitrate in the Southern Uplands, to find a piece this large definitely is!
Chalcopyrite is similar to pyrite and to Bornite, which you may know as peacock ore. Though Bornite shimmers multiple colours on a kindle of blue base, chalcopyrite retains the golden base colour of pyrite. 
However, hit it with acid and you maybe able to influence the colours. We don't advise you do this, by the way. It's already got blues and greens, orange, gold, and white through it.