Mosaic Art Source mosaic definition:
smalto (pl. smalti) – smalti is characterized by its dazzling range of brilliant opaque colors. Smalti is prepared by adding crystalline material (corpo) and coloured material (anima) to the colourless or coloured fused glass. Smalti is literally available in thousands of colors, is a very stable glass, easy to cut and very durable. m.a.s. mosaic glossary
Mosaic Art Source Ravenna, Italy mosaic photo archives.