This cufflink contains shows both sides of a King Edward First Hammered penny. One side is on one cuff link and the other side is showing on the other. Both cuff links contain a full coin glued stongly onto the cufflink. Here's the description of the King Edward I coin that is on this cuff link ...
Edward I Hammered Penny Class 9a, 18 mm. S1407. Minted in Chester with writing on reverse CIVI TAS CES TRI