A silver-gilt convex shield with a central medallion cast in high relief showing Apollo in a quadriga, surrounded by stars and female figures representing the constellations. The broad border is cast in low relief with scenes of human life (a wedding and banquet, siege, ambush and engagement, harvest, judicial appeal, vintage, oxherds defending their beasts and a Cretan dance), within an outer border of stylised waves and a broad reeded rim.

In the eighteenth book of the Iliad, Homer vividly described a legendary shield made for Achilles by the lame god Hephaestus and brought down to Earth by Thetis (mother of Achilles), together with other specially-forged armour. The shield was said to have been a mirror of the world of gods and men, within the 'mighty Stream of Ocean' and although Homer described its appearance in great detail, the precise relationship of the various elements was unclear. In 1810 John Flaxman received the first of a number of payments from Rundells to 'reconstruct' this mythical shield from Homer's description. Although Flaxman was said to be a keen Greek scholar who spent many evenings reading aloud (in Greek) from the Iliad, it is probable that his chief source for the design was the narrative in Pope's translation of 1715-20.

The final design was not completed until 1817; somewhat unusually, Flaxman then modelled and cast it in plaster himself. This shield was the first in a series of silver-gilt and bronze casts, and was completed in 1821, when it was prominently displayed at George IV's coronation banquet. Flaxman was said to have been justly proud of his design, which was subsequently described by Rundells as a 'masterpiece of modern art' and considered by many as one of the artist's most successful works. Other silver-gilt versions of the shield were made in 1821/2 for the Duke of York (now Huntington Collection, San Marino), and in 1822/3 for the Duke of Northumberland (now Al-Tajir Collection) and the Earl of Lonsdale (now National Trust, Anglesey Abbey). There is an early bronze cast of the shield, subsequently silver plated, in the Royal Collection (RCIN 31606)