Burnisher
a tool for smoothing or pressing down surfaces to close the pores or obliterate lines or marks. The engraver's burnisher is made of steel, elliptical in cross section, and coming to a dull point like a probe. Some burnishers are made of the canine teeth of dogs. Burnishers of bloodstone are used for putting gold leaf on china ware.
Agate burnishers are used by bookbinders. The gilder's burnisher is of agate or porphyry.