Calendar for the single year of 1830. The calendar is made from a disc of tin. On one side of the calendar is a table, which is shaped like a shield, with the months in three letter abbreviations and a table with the numbers for the number of days. Around the edge of the table are inscriptions of dates including Easter and information about an eclipse. The other side three rings of inscription relating to the phases of the moon. At the centre if a profile image of King George IV.