Female dynasts are titled princess ("prinsessa"). The Swedish Succession Act was altered in 1980 to allow for female succession to the throne. King Gustav III revived a tradition from the time of Gustav Vasa and the medieval era by giving male heirs to the throne ducal titles of Swedish provinces. The difference between the ducal titles from the Vasa era and those granted by Gustav III is they now are non-hereditary courtesy titles given at birth. Since 1980, they have been conferred to all royal heirs, male and female. The wives of royal dukes have always shared their husbands' titles; the husbands of royal duchesses have done so as of 2010. The regalia of Sweden are kept deep in the vaults of the Treasury chamber (), located underneath the Royal Palace in Stockholm, in a museum which has been open to the public since 1970. Among the oldest objects in the collection are the sword of Gustav Vasa and the crown, orb, sceptre and key of King Erik XIV. The Regalia is state property and the government authority which holds it in trust is the Legal, Financial and Administrative Services Agency. The last king to have been crowned was Oscar II. His son and successor, Gustaf V, abstained from having a coronation. While the crowns and coronets have not been worn by Swedish royalty since 1907, they are nevertheless still displayed on royal occasions such as at weddings, christenings and funerals. Until 1974, the crown and sceptre were also displayed on cushions beside the Silver Throne at the annual solemn opening of the Riksdag (). The Royal orders have a historical basis, dating back to the 1606 founding of the now extinct Jehova Order. The Royal Orders of Knights of Sweden were only truly codified in the 18th century, with their formal foundation in 1748 by King Frederick I. In 1974 the Riksdag significantly changed the conditions and criteria under which orders and decorations could be awarded: that no Swedish citizen outside the Royal Family is eligible to receive such decorations. The Order of the Seraphim () is only awarded to foreign heads of state and members of the Swedish and foreign royal families, while the Order of the Polar Star () can be bestowed on any non-Swedish citizen. Following the reforms, the Order of the Sword () and the Order of Vasa () are no longer conferred: officially they have been declared as "dormant". Since 1975, H. M. The King's Medal () is the highest honour that can be awarded to Swedish citizens other than members of the Royal Family.