Cloth Seal, Alnage/Subsidy for Faulty Cloths, Image & Found by Adam & Lisa.
"I found this on a local site [Derby area], the other evening. I think it's some kind of seal. 28mm, between 1 and 2mm thick (5mm inc. the projecting bit on the back) and 11.4g. Not sure what the design is, there is lettering around the outside, maybe a bust in the centre?"
See Nos.110 & 111, Fig.25 p.176 (pictured below), Geoff Egan, Lead Cloth Seals and Related Items in the British Museum. "Unprovenanced alnage seals - for faulty cloths (with bulbous F's)"
"Alnage/Subsidy Seals for Faulty Clothe. Probably late-medieval (Legends and Fs are in Lombardic lettering). Special seals for faulty cloths are first mentioned in Statute 4 Ed.IV cl (1464). The central F on the following seals, standing for 'faulty', is specified in Statute 5 and 6 Ed. VI c6 of 1551-2, though it had probably been in use for some time by then. Seals with a smaller F probably continued in use well into the late sixteenth century.... Over half the alnage seals in groups found in Gloucester and Salisbury have these 'faulty' stamps (this seems to be in contrast to London finds, among which they are somewhat less common).......
No.110 Fig.25 [middle one in picture below] D.29mm//29mm; two pairs of pellets on strip. crown over ornate shield with arms of England, rose and sun to sides, ...LNAGII PANNOR'IN COM... around // large letter F with sun and rose to sides, rose S'SVBCID(II PAN)NOR IN COM ...(T) around. The sun and rose may indicate the late fifteenth century..., though the stamp may have continued in use for some time afterwards.
N0.111 Fig.25 [bottom one in picture below] D.25mm//missing. crown over ornate shield with arms of England, rose and sun to sides, rose S'SVBCIDII PANNO(R IN COM ?DO)RS around ?? (on rivet) large, bulbous letter F. Textile imprint: plain tabby weave; c.14 warp and c.12 weft threads per 10mm.... (/)Late fifteenth-century. Perhaps Dorset, though the reading cannot be regarded as certain (Somerset is a less likely alternative)."
Circumstantial evidence has been found for the careful removal of this type of seal, no doubt to replace them with ordinary alnage seals to get the better price of a fully compliant cloth, see p.278, Carter, T., Egan, G. and Medlycott, M., Cloth seals and other metal-detecting finds from Saffron Walden, Essex Archaeology and History, vol.33, 2002.
See BSG.CS.01217 for another of this type of seal.