A virtually identical urn based on the Borghese vase in the Louvre is illustrated in a French catalogue of 1805 advertising porphyry from Alvdalen in Sweden, is illustrated in Bukowski's Exhibition catalogue, Porfyr, (No. 24). A pair of virtually identical vases from the collection of the late Dowager Countess Howe were sold, Christie's London, 4 June 1992, lot 102.