A late 18th century flat circular box and cover

A late 18th century flat circular box and cover, with a bright engraved border, initialled "TCL", the base with a narrow slot in each side (probably a seal holder, the slots to allow a tape or ribbon to pass through), traces of a mark in the base, unascribed c.1790, 1.5in (3.7cm) diameter, 0.5oz.