à effet-camée

OBS: effet-camée : Apparence de certaines pièces en or et en argent de qualité épreuve numismatique sur lesquelles le motif mat et pâle apparaît en net contraste sur le champ poli et foncé.

OBS: cameo contrast: The contrast in appearance between the devices and the fields.
OBS: The ""frost"" or ""frosting"" is a matte type surface on the devices of a cameo coin and can range in appearance from white to gray (less white) to silver (no white). The fields of a cameo coin can range from ""black"" (deep mirror) to silver-appearing (semi-prooflike). The degree of contrast can be subdivided into degrees as ""slight"", ""excellent"", and ""outstanding"". An outstanding contrast is also known as ""black and white"".