Thank you for viewing! This is a set of dichroic glass arête pieces (approximately 40g). (The expansion coefficient is unknown.) Recommended for creating accessories, glass fusing, and other artwork. The sizes are mainly fragments of 1-5 cm, and they include a variety of colors and textures as shown in the photos. The photos were taken in natural light, but the actual pieces may appear more vivid. We will carefully package and ship them, so thank you for your understanding.