The method of manufacturing a timepiece shaft (1) includes grinding a ceramic piece, especially to form a balance shaft (1), having a functional portion (2a; 2b) including at least one part (221a; 221b) of a pivot-shank (22a; 22b) and/or at least one part (211a; 211b) of a pivot (21a; 21b), the first functional portion being made of ceramic and a first outer diameter (D1) of the first functional portion being less than 0.5 mm, or less than 0.4 mm, or less than 0.2 mm, or less than 0.1 mm.