Buttplate from a sea-service musket. This is one of a group of pieces extracted from marine concretion, all apparently from the same weapon; the group comprises numbers ZBA0442-0445. Recovered from the wreck site of an unidentified merchantman circa 1780-1815 in the South Edinburgh Channel, Thames Estuary, in 1975. Other items in the museum from the same wreck include: REL0628-0689, REL0769-0771, ZBA0439-0445.