In addition to the uncoated version, we also offers from Wissmach a series of glasses with an iridescent coating. Wissmach calls the coating on non-fusible glass "iridescent" and on fusing glass "luminescent". In the case of luminescent, the coating should point downwards or be covered when melting so as not to burn. Again, of course, while not every glass is suitable for fusing, any fusible glass can be used in the other techniques.