Compare with Marsigli's full-length miniature of Princess Louisa of Stolberg, from the Pierpont Morgan Collection, now in the Walters Art Museum, Baltimore. For Marsigli's full-length portrait of King Ferdinand IV of Naples, with further information on this interesting painter, see the sale catalogue of the Brewster Collection, Sotheby's, Geneva, 15 November 1995, lot 290.
L. Schidlof (The Miniature in Europe, Graz, 1964, II, p. 534) mentions that Marsigli's portrait of Count Shuvalov was engraved (by Alexius Giardoni in Rome).
Count Ivan Ivanovich Shuvalov was called the Maecenas of the Russian Enlightenment and the first Russian Minister of Education. Russia's first theatre, university, and academy of arts were instituted with his active participation. At the age of 22, he had become the lover of Tsarina Elizabeth Petrovna, 27 years his senior. He never married.