ashtray or empty pocket signed JP-MD numbered 12

Art deco cup or ashtray with lying on one side, signed jp - md number 12, artist of the late nineteenth century (pierre jules mène), I think the object is plaster but it is relatively heavy, dimensions 18x13x6 cm approximately, no defect provide only a cleaning because I just passed it with soapy water after a long stay in a garage!.

Ref. : VT4GD9PD