From a series of seals with Norwich or 'Norfolk' arms and two large initials. A parallel is recorded as seal 1199 in Provenanced Leaden Cloth Seals by Geoffrey Egan, Sub-Department of Medieval Archaeology, University College, University of London, submitted for the degree of Doctor of Philosophy, 1987, but that seal only reveals the last number of the date (---7) and the first initial is unclear, making the seal shown here a much better example.
The castle is employed for the arms of both Norfolk and Norwich with a lion passant beneath the castle signifying Norwich, however, many seals without a lion visible may still be for Norwich with poorly registered stamps. This seal clearly has room for a lion and is, comparatively, well stamped but shows nothing other than a few raised markings to the lower right. This would suggest a Norfolk seal but Egan in the reference above has classed it as a Norwich seal but not with certainty.
The escallop is thought to be the privy mark of the die engraver who was active c. 1628 to c. 1640 and apart from other seals his mark can also be found on communion cups, see Wilfred Joseph Cripps, Old English plate: Ecclesiastical decorative and domestic: its makers and marks, 1967
This seal is not from the similar series that show the initials of the Mayors of Norwich from the late sixteenth to the early seventeenth centuries. It is not known what the initials on this series stood for.