Zultanite is an extremely rare gemstone used in jewelry design, and was a popular choice at the 2011 Couture conference, which features the most unique, innovative and inventive jewelry design. Famous jewelry designers such as Stephen Webster, Erica Courtney and Rhonda Faber Green all incorporated zultanite into their collections. Zultanite changes color in light, ranging from a kiwi green with flashes of yellow in sunlight conditions to raspberry hues in candlelight.