1780 Austria, SF 1 Thaler Maria Theresa Austrian Empire Silver Coin

Maria Theresa Thalers are silver bullion coins that were first minted in 1741 and continue to be produced today. The coin is named after Maria Theresa, who was the Archduchess of Austria and Queen of Hungary and Bohemia from 1740 to 1780.
While the coin has the year 1780 on it, this date is a "frozen date" and does not necessarily indicate the year it was minted. Production of the coin continued with the 1780 date even after Maria Theresa's death. The coin was used for centuries as a trade currency in various parts of the world, especially in the Middle East and Africa. It was so widely trusted that merchants in some regions would not accept any other type of currency.
The visible text on the reverse of the coin, "ARCHID. AVST. DUX. BURG. CO. TYR. 1780. X.", is an abbreviation of the Latin phrase "Archidux Austriae, Dux Burgundiae, Comes Tyrolis," which translates to "Archduchess of Austria, Duchess of Burgundy, Countess of Tyrol". The "X" was added in 1750 to indicate a new debased