Multi-piece solid golf ball

A multi-piece solid golf ball comprising a solid core, an inner cover layer and an outer cover layer, wherein the solid core is molded from a rubber composition comprising

• 100 parts by weight of a base rubber composed of
• (a) 20 to 100 wt % of a polybutadiene having a cis-1,4 content of at least 60% and a 1,2 vinyl content of at most 2%, having a viscosity η at 25° C. as a 5 wt % solution in toluene of up to 600 mPa·s, being synthesized using a rare-earth catalyst and satisfying the relationship:
• 10B+5≦A≦10B+60,
• wherein A is the Mooney viscosity (ML1+4(100° C.)) of the polybutadiene and B is the ratio Mw/Mn between the weight-average molecular weight Mw and the number-average molecular weight Mn of the polybutadiene, in combination with
• (b) 0 to 80 wt % of a diene rubber other than component (a),
• (c) 10 to 60 parts by weight of an unsaturated carboxylic acid or a metal salt thereof or both,
• (d) 0.1 to 5 parts by weight of an organosulfur compound,
• (e) 5 to 80 parts by weight of an inorganic filler, and
• (f) 0.1 to 5 parts by weight of an organic peroxide;
• the inner cover layer has a Shore D hardness of 10 to 60;
• the outer cover layer has a Shore D hardness of 50 to 80;
• and
• the outer cover layer has a higher Shore D hardness than the inner cover layer.