Citrus green glass if fired in a kiln with metal oxides on the surface of a second layer of glass. Using temperature and time the artist and get different effects with the design. Here, the artist, Kathy Seff, used a lower teperature and less time to keep some texture on the edges and showcase the layered effect of the design. Handmade and signed by artist. Seff Designs is also available at Razor located on 5th Ave in Park Slope Brooklyn. Glass measures appx 1/2" square.