Golf ball 1 includes a core 2 and a cover 3. The core 2
has two layers including a center 4 and a mid layer 5. The mid
layer 5 is formed by covering the center 4 with two half shells comprising
a rubber composition, and by compression and heating of the center 4 and
half shells in a mold. The rubber composition contains solid particles dispersed
therein. The solid particles have a ratio "D/T", i.e., a ratio of the particle
size D to the thickness of the mid layer T, of equal to or greater than 0.3. Upon
molding, the solid particles inhibit the center 4 to approach a cavity face.
Accordingly, deviation of mass of the mid layer 5 can be suppressed. The
solid particles have a ratio "W/T", i.e., a ratio of the radial width W thereof
to the thickness of the mid layer T, of from 0.3 to 1.0.
