File:Manilla showing decoration on band (FindID 100482).jpg

English: Cast copper alloy penannular arm band or arm-ring made up of a curved flattened rod, convex in section, with expanded and flattened terminals. The terminals and the band are decorated with punched dots and incised rouletting in radiating lines on the terminals and criss-crossed across the band which makes it appear like rope.

The terminals are 25 mm in length and 18.6 mm in width. The manilla is 180 mm in total length, 12.5 mm in width and 5 mm in thickness and has a diameter of 64.4 mm.
This arm-ring may have been worn, but it also may have been made from or used as a 'manilla'. Manillas were used as a form of money to trade for slaves on the West African coast from the time of Henry VIII right up until World War II. They are hard to date as they were made in the same way, using the same metals with the same decoration for a long time. The status of copper and its alloys in Africa was always high, so anything made of these metals would have had some value (Len Pole, pers comm).

Manillas of this type were mainly made for trade between Britain and West Africa in the 18th or 19th century, like examples in the Royal Institution of Cornwall's collections that came from Africa and were used as bracelets before being used as tokens for money. It could have come from the shipwreck of the 'Duoro' which was en route to Africa with other manillas on board when it was lost with all hands off Crebawethan, Western Rocks (to the southwest of the findspot), Isles of Scilly on 27th January, 1843.