The Golden Tiara was a gold and silver papal tiara given to Pope Leo XIII in 1903.
The tiara was given by the Vicar-General of Rome on behalf of the world's Catholics to commemorate the Pope's Silver Jubilee as pope. It was the fourth papal tiara given to Pope Leo during his twenty-five year reign.
It is not known if the Pope ever wore the Golden Tiara. He died in the year the tiara was given to him.
While Leo's successor, Pope Pius X, was shown in drawings wearing the Golden Tiara, it is not known if he actually ever wore it.
No papal tiara has been worn since June 1963. Though unworn, popes have not been prohibited from opting to wear any tiara, including the Golden Tiara, should they choose.
References
Golden Tiara Wikipedia(Text) CC BY-SA