Yorkshire 6, Sheffield (Dalton & Hamer, page 320)

Denomination: penny, scarcity: Very rare (RR)
6.  O: An oval shield inscribed BRITAIN between four flags inscribed AMERICA
       HOLLAND FRANCE POLAND. Date at sides 17-92. UNITE & BE FREE TO PERSEVERE
       IS TO CONQUER. (Same as rev. of No. 4).
    R: A lion rampant, supporting a shield, &c.

No. 6, RR. 

Keywords

america holland france poland,1792,unite be free to persevere is to conquer,revolution penny