The oval gem is carved with a seated figure of Ceres, the goddess of agriculture and fertility, holding wheat in her left hand, her right hand resting behind her on her stool, set in a substantial gold ring with an open back, with hallmarks.
Tasmanian private collection of a lady, acquired in London circa 2010, mounted in the 19th century
For a closely-related gem of Ceres seated on a stool and holding wheat, see Beazley Archive Gem Database no. 3.I.D.15: T. Cades, Impronte dell' Instituto, Libro 3, classe I, D, no. 15