An early nineteenth century Vauxhall glass butterfly brooch, composed of wings and body with large-faceted deep red mirrored glass surrounded with smaller circular mirrored glass, with brass antennae, affixed to a perforated brass backplate, 2 in by 2 in, unmarked, circa 1830. 

Vauxhall glass, or mirrored glass, notable for its highly reflective appearance and produced in an array of colors including black, red, silver, green, purple, and blue, was produced by the Vauxhall Glassworks from the mid-eighteenth century through the mid-nineteenth century. The Vauxhall Glassworks abutted the Vauxhall Pleasure Gardens in London where jewelry was often sold as souvenirs to visitors. Later pieces may be easily identified as they were stamped on the reverse with English registry marks, earlier pieces lack such marking.