Swaging tool forming a stamp, and associated stamping process

A swaging tool (1) forming a stamp for a metal movement-blank, the swaging tool comprising:

• a lower unit (2) and an upper unit (4),
• the lower unit being arranged to be able to form a bed (10) intended to receive the metal movement-blank (12), the upper unit being equipped with an upper die (26), intended to swage the metal movement-blank in place in the bed (10) of the lower unit (2), and mounted movable along a movement axis (B-B′);
• wherein the lower unit (2) includes pliers (14) formed by two arms (16A2, 16B2) mounted movable, in a perpendicular plane to the movement axis (B-B′), between an opening position wherein the two arms of the pliers are moved apart, enabling a placement of the metal movement-blank between these two arms, and a closing position wherein the two arms (16A2, 16B2) of the pliers are moved closer together and then define, along the movement axis (B-B′), an upper region and a lower region of the bed (10) separated by an opening (18), the dimensions of which are less than the corresponding dimensions of the lower region and the corresponding dimensions of the upper region of the bed, the two arms in the closing position thereof forming, at least in said upper region of the bed, a lower die for the metal movement-blank.