Use individually or layer transparent glass sheets to create varying hues, tones and saturation. This 90 COE fusing glass is designed for use in the Fuseworks Kiln. TO USE: Place glass on a flat cutting surface. Score glass using a glass cutter to desired shape and break. Layer glass on kiln paper inside kiln and fuse. Made with Fuseworks 90 COE glass, specifically designed and tested for use in the Fuseworks Microwave Kiln. Contains 4 pieces. Made in the USA.