The present invention relates to a gray gold alloy free of nickel and copper having a hardness that is suitable in particular for watchmakers and jewellers. Said alloy consists of (in wt %): more than 75% of Au; more than 18% to less than 24% of Pd; more than 1% to less than 6% of at least one element selected from among Mn, Hf, Nb, Pt, Ta, V, Zn and Zr; optionally, no more than 0.5% of at least one element selected from among Si, Ga and Ti; and optionally, no more than 0.2% of at least one element selected from among Ru, Ir and Re. The invention also relates to a method for preparing said alloy.