Jackson records a silhouette of William IV, ‘very delicate work in black and gold with elaborate detail’. She supposes that this was the work of John Harris the younger, who attended the Royal Academy Schools and is known to have worked in several fields of art, including portraits and miniatures. No other evidence of his silhouette work has been uncovered.
Source: McKechnie (Author of, British Silhouette Artists and their Work 1760-1860)
Harris, John (McKechnie Section 1)