AgCuIS-II + 12 HNVO3 AgNVO3 + CuII(NVO3)2 + H2SVIO4 + 9 NIVO2 + 5 H2O

This is an oxidation-reduction (redox) reaction:

CuI - 1 e- CuII (oxidation)

S-II - 8 e- SVI (oxidation)

9 NV + 9 e- 9 NIV (reduction)

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