Cloth Seal, Leiden, Double Headed Eagle, Image & Found by Markus McMillan.
Found on Thames foreshore.
Leiden cloth seal. Double headed eagle on one side and LEY with DEN beneath on the other. Below the DEN and slightly overlapping it is a circular stamp with the letters C and a possible flower above D and possibly G.
From finder:- "the small inner circle reads C then looks like an anchor or you're right a flower then underneath DG"
No. 322, Fig. 43 Geoff Egan, Lead Cloth Seals & Related Items in the British Museum, shows a Leiden seal with a small secondary stamp of a double headed eagle proving that this symbol was used by this city along with the more common crossed keys and lion rampant holding sheaf of arrows.