In 1637, Emperor Ferdinand II, Holy Roman Emperor, archduke of Austria and king of Bohemia and Hungary, died.

CNN: Saturday,

Although it is not known exactly when the diamond entered the House of Habsburg, it has been officially recorded as the property of the Archduke Joseph August of Austria, Palatine of Hungary (1872-1962), and was subsequently named after him.

FORBES: 76-Carat Archduke Joseph Diamond Expected to Fetch $15 Million

It was named after Archduke Joseph August of Austria, a prince of the Hungarian line of the Habsburgs, who reportedly deposited it in a bank vault in 1933.

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