3 CuFeS2-II + 28 HNVO3 3 Fe(NVO3)2 + 3 Cu(NVO3)2 + 16 NIIO + 6 H2SVIO4 + 8 H2O

This is an oxidation-reduction (redox) reaction:

6 S-II - 48 e- 6 SVI (oxidation)

16 NV + 48 e- 16 NII (reduction)

CuFeS2 is a reducing agent, HNO3 is an oxidizing agent.