C OMark wording
Undated
C O
Seen on objects dated 1694–1695.
silver
Attributed as "possibly John Cory" by Mitchell Mitchell, David M. - Silversmiths in Elizabethan and Stuart London: their lives and their marks, Boydell Press, 2017 but note that Cory's Britannia Standard mark, " crowned", features a very similar which makes the attribution very likely.