In her crystalline work, Alexis Templeton explores the cool blues, greens, and whites of water and ice. Two key elements are needed for this "Jack Frost" effect: the right glaze recipe, and a modified cooling process. A glaze is simply a glass layer over a clay body, but normally glass doesn’t crystallize on cooling. Adding zinc oxide to a glaze recipe, and stalling the cooling at specific temperatures, stimulates crystal growth.