Rarely traded Prussian forgery of King Stanislaw August's first gold coin. Made in the era, to the detriment of the issuer, being a souvenir of Frederick II's economic war against Poland.
A variety with a distinctive portrait of the king described by the author of the SAP Silver Coins blog as a"beak". According to his searches, clearly rarer than forgeries with an "angel" type portrait (only 12% of the counterfeit population).
A very nice piece, given the use of undersampled silver.