Loredano Rosin (Italian/Murano, 1936-1992), Calcedonia Glass Cobra Sculpture, third quarter 20th century, composed of aubergine and mauve glass, the cobra depicted with his head up and his hood spread, with an engraved "Loredano Rosin" mark, h. 19-3/4", w. 9-3/4", d. 10-3/4". The production of Calcedonia glass is a difficult technique which incorporates a precise amount of silver nitrate to produce the luminous, yet ultimately uncontrollable, striations of color. It was originally created in the mid-15th century in Murano, Italy; the technique was forgotten until the 19th century when it was briefly revived by the glass master Lorenzo Rad (1803-1874). In the mid-70s, Loredano Rosin began to work with Calcedonia glass, believing the technique enhanced the smooth, fluid forms of his hand-sculpted glass. Rosin, a native of Venice, was trained - along with his siblings - in the ancient Murano glass blowing tradition. After serving his apprenticeship, during which he experimented with glass sculpting, he eventually opened his own studio. The cobra presented here, with its unexpected streaks of umber, purple and green, is a wonderful example of the serendipitous nature of this technique.