History and Techniques of Murano Glass

Rock crystal, a natural quartz, is usually colorless and translucent, composed of pure silicon. Since ancient times, glassmakers have sought to imitate it. Carved rock crystals from Egypt, Iraq, and Persia inspired cut and ground glass. However, Egyptians did not favor rock crystal, explaining the scarcity of local archaeological finds. During the Renaissance, rock crystal was highly valued, with notable pieces mounted with precious metals by Benvenuto Cellini (1500-71). Later in Bohemia, Caspar Lehmann introduced wheel engraving on hard stones and then on glass (potash rather than soda). The term 'crystal' for Venetian glass decolorized with manganese was used due to its resemblance to rock crystal, though this glass was too fragile to be worked and engraved like quartz. In 1674, a patent was granted to George Ravenscroft in England for producing a crystal-like glass resembling rock crystal. In German, it is called 'Bergecristal', in French 'cristal de roche', and in English 'rock-crystal'.