Made of crystal glass, crystal clear, bright colors, rounded corners treatment does not hurt your hand. Exquisite design looks very beautiful. Freely assembled and moderately sized, perfect for DIY art projects as well as customized creations at home! Crystal clear and bright colors, can be used for home decor, art creativity, DIY handmade photo frames, coasters, vases and other DIY mosaic projects! The back of the pellet does not come with self-adhesive, you need to buy or prepare glue to stick it.