A proton has spin and magnetic moment just like an electron. Why then its effect is neglected in the magnetism of materials?

Hint: The mass of the proton is much greater than the mass of the electron.
Step 1: The comparison between the spinning of a proton and an electron can be done by comparing their magnetic dipole moment which can be given by:
          M=eh4πm or M1m       eh4π = constant
               =Me1837Me                      Mp = 1837 me
   Mp<< Me
Thus, the effect of magnetic moment bf proton is neglected as compared to that of the electron.