Gravitomagnetic clock effect in the orbit of a spinning particle orbiting the Kerr black hole

We present a particular derivation of the gravitomagnetic clock effect occurring in circular equatorial orbit of a spinning test particle orbiting the Kerr black hole. The result, valid for parallel spins of the bodies, indicates that spin of the orbiting particle contributes a significant amount, that is opposite in sign of the ordinary gclock effect, to the gravitomagnetic clock effect