Wissmach Glass Black Iridescent Stained Glass Mosaic Tiles are 1/8 thick, opaque, iridescent on one side and black on the other. The iridescense in this glass gives a bright pop of color to your project. You never know if you will see green, blue, pink or yellow as light hits your artwork from different angles. Stained glass mosaic tiles work wonderfully on stepping stones, hanging art, furniture, picture frames, drink coasters, mirrors and more! This glass is suitable for interior and exterior use.