Mould lines and vent holes.
Mould-made figurines show a seam down the sides and often a firing vent hole in the back. Hand-modelling leaves finger marks. The fabric in a fresh break — colour and inclusions — places the workshop better than the subject does.
Slip, white ground, and painted colour sit on the surface and may be worn or later; original pigments are fragile and easily lost to over-cleaning, so leave any surviving paint strictly alone.
Famous types attracted famous fakes: Tanagra-style figures were forged in quantity in the nineteenth century, often cast from originals. Softened detail, wrong fabric, and too-even “root marks” are the usual tells.
For high-value pieces, thermoluminescence (TL) testing can establish when the clay was last fired. Short of that, record fabric, seams, vents, and pigment traces, and let the attribution carry an honest “probably”.
Identifying pottery and ceramics
Identifying amphorae and transport pottery