Glass has been used for centuries in mosaics. Mosaics are typically 3” or smaller in size and applied to a mesh or plastic sheet. There are four types of glass tile, smalti, fused, sintered, and cast. Smalti is a small format tile that is typically textured and colorful. Fused is flat tile that is fired in a furnace. Color is used added to underside of these tiles. Sintered tile is made by pressing glass powder into dies and then heated to fuse the particles. Color can be added before or after heating. Cast tile is made by inserting chunks of glass into a mold. The mold is heated until the pieces melt into each other and become a coherent mass. Glass can also have two different treatments slumping and etching, Slumped glass is usually achieved by melting plate glass into relief molds at relatively low firing temperatures. On cooling, the glass assumes a distinctive textured finish. Etched glass is a process of applying a thin, translucent layer on the surface of a tile. It gives the glass a cloudy or matte finish. It can be applied in shapes to give a unique look. Glass tile is only recommended for wall applications.