Diamond Crown of Bulgaria

The Diamond Crown of Bulgaria () is a royal regalia (along with the Sceptres of Ferdinand I and Boris III), that existed during the Bulgaria monarchy from 1878 to 1946. 
The crown originally belonged to Queen Marie Antoinette of France. It was given to Princess Clémentine of Orléans as a dowry together with a golden carriage also belonging to Marie Antoinette. Both of those items ended in the possession of the Bulgarian Royal Family. The carriage is currently on display at the Sofia History Museum. 
The original top of the crown was replaced from the French Fleur-de-lis to the Bulgarian boll with a cross on top of it. The crown was first used by Princess Marie Louise of Bourbon-Parma on her wedding to Prince Ferdinand I. It later passed to and was used by Ferdinand's second wife, Princess Eleonore Reuss of Köstritz. 
The current whereabouts of the crown is unknown.