Chalcedony dolphin on wave, horizontal version. Chalcedony was invented in Murano in the 15th century and rediscovered by Maestro Lorenzo Radi in the first half of the 19th century. Its difficult preparation involves the addition, in the glass melting crucible, of various metallic compounds and silver salts that create the shades of colors. Each master has his own formula and color shades. This piece was created and signed by Maestro Andrea Tagliapietra. Warranty certificate