Cartouche
Cartouche - When used in the context of antique silverware, it refers to the centre-piece / ornate frame-like area on the surface of an object on which engravings (such as names/monograms) are made.
From time to time, antique objects can be found with an unengraved cartouche - this can be ideal for some who may wish to add their own engravings/present the item to someone.
On the other hand, depending on the monogram (such as a historical figure's name) the marked cartouch can add significant value to the initial antique object.