Our mosaic tiles are cast from colored vitreous glass in the centuries-old tradition of master glassmakers. Vitreous glass tiles will last nearly forever - their rich colors never fading. They are waterproof and useable indoors or outdoors. The glass is fired in high-temperature kilns using the finest of raw materials resulting in mosaic tiles that are semi-transparent and light reflective. This gives our tile a special luminous quality with rich color-depth and consistency. Designed for safe and easy cutting, nipping, and shaping, our tiles can be applied to any reasonably smooth surface. These tiles are shiny smooth on the front side and textured on the back for better adhesive grip. The edges are miter-beveled for making clean right angle corners. Our vitreous tiles are available in 3/4-inch (20 mm) and 3/8-inch (10 mm) (mini) sizes. Plainly put, there is no finer quality mosaic glass tile to be found anywhere in the world.