Commemoration of the siege of Groningen; history medal made after a royal thaler; Brass diamond-shaped history medal with rounded corners. Front: double-headed eagle with coat of arms for chest under the letter G inside an inscription. Reverse: inscription: '1577 Gronningen was thought to be Laet no more servants as Du biste machtich Innovt den 18 mar 1657; Groningen; anonymous; 18-Mar-1657; brass (alloy); engraving; h 5.3 cm x w 5.3 cm x w 15.71 gr