An oval copy after Franz Xaver Winterhalter's rectangular bust-length oil portrait of the Baron painted for Prince Albert in 1848 (405830; Royal Collection).

John Simpson (1811-after 1871) was trained as a porcelain painter at the Derby porcelain factory before moving to London in 1845. He soon established a practice as a miniature painter specialising in works on enamel, and fulfilled the first of many commissions for Queen Victoria in that year. He is last recorded describing himself at the end of his career as a 'photographic artist' (1871 census return); the date of his death is not known.

Signed, dated and inscribed on the counter-enamel in black paint: The Baron Stockmar / aet: s 60 / 1847 / Simpson after Winterhalter / 1848