Horses in Pasture on Mother of Pearl, sparkling white shell. The base of the button is heavy, smooth, durable, flat, high quality, bright white shell, onto which the artwork is attached, followed by an application of topcoat for a bit more gloss and protection. The glow of the natural shell shows through. Beautiful! 1-3/8" diameter, almost 1/8" thick, shank back button. Hand made in the USA by Susan Clarke.