Producing highly distinctive, high quality profiles on flat, convex glass and less commonly ivory, Finnish-born JACOB SPORNBERG (ca.1768-after 1840) worked primarily in Bath and Cheltenham. The quantity of extant works evidence his output was prolific and though substantial biographical detail is already recorded, current research discovered him working in London and latterly becoming an architectural modeller in limewood.
To be continued.
Source: McKechnie (Author of, British Silhouette Artists and their Work 1760-1860)
Spornberg, Jacob (McKechnie Section 3)