A cool Bulldog pin ~ pendant, love those jowls!  It measures 1 5/8 x 2 1/4 inches.  The back is stamped BEST; it has an odd C clasp, push the pin shaft down until it snaps into place, pull up firmly to release; probably easier to add a chain and wear as a pendant.  It looks like tarnished silver with gold-tone ears, collar, feet and tail; it is not marked silver and I do not believe it is.