Morjo™ Iridescent Glass Mosaic Tiles 3/4 inch (20mm) are smooth, richly colored opaque glass tiles with a subtle iridescent gloss on one side. Each 1/2 pound contains about 75 tiles. Embossed ridges and grooves on the back help adhesives bond securely. Note: the BLACK color is more GLOSS than Iridescent, but it looks good with the other colors. Click on a color to see the full product description.