This is a British Royal Horticultural Society (RHS) medal. It is a silver medal, likely awarded by the Horticultural Society of London (later the RHS). The design, featuring a central figure of Ceres (goddess of agriculture) surrounded by putti holding flowers and fruit, was created by William Wyon, a renowned Royal Mint engraver. The artist's signature F.
Is visible at the bottom left. The edge inscription "ROYAL MINT 1836" indicates its striking date.