Current knowledge

Lord Darnley

Christie's 21st March 1975, lot. 57 or Lord Bolton, Wensleydale

Note that the miniature cited here is only a possible match with the record. The image corresponds to the Christie's lot. Two portraits of Lord Darnley are recorded in the Sale [WS 65, №78 and WS 204, №300]. One of the Bolton collection's two three-quarter length Lord Darnleys was presented by the Duke of Lennox to Charles I in 1640; the other was also apparently in the King's collection. See Roy Strong, Tudor and Jacobean Portraits,  1969, p.60-1

Sale Inventory c.1649-51
Walpole Society reference (1972):