Since the middle ages, tourists have traveled to the Italian city of Venice in awe of its spectacular glassmaking industry. Then, glass was considered a novelty, tangible only to the most affluent consumers – now, tourists simply appreciate the history, beauty, and technique that made Italian crystal the elegant art form that it is today. As a frequent tourist destination for travelers on their way to the Holy Land, Venice attracted affluent visitors to its religious relics as well as to its glass workshops, where experts employed only the finest materials, the most advanced technologies, and the most perfected techniques in creating the most luxurious glass articles to be found anywhere in the world. v guard vg crystal Here, the artisans had so perfected the art of glassblowing – using an endless range of tints to color their products that were as transparent as nature’s own crystals – which their beautiful, delicate works could pass for diamonds, rubies and emeralds, even among some of the finest connoisseurs of precious stones. An ordinance enforced in 1271 dictated a ban on foreign glass imports, a ban on foreign glassmakers seeking work in the city, and strict rules and restrictions for approved glass guild workers. These restrictions limited the production and distribution of raw goods as well as finished products, and also limited travel outside of the island of Murano. Guidelines for customer contact were rigid, and a division of labor not only protected any one worker from possessing too great a wealth of skill and information himself, but also fostered specialization that led to increased productivity and higher quality of the final pieces of art. In exchange for their specializations and rigid living conditions, workers and their families enjoyed special privileges such as a pathway for daughters to marry into nobility and increase the family’s social status and political power. On the other hand, if the city’s artisans – who composed about half of the island’s population – defied any of the strict regulations, disclosed any glassmaking secrets to outsiders, or even attempted to leave the island, they placed their lives in jeopardy. City’s officials would go so far as to put them to death to protect the secrets of their precious glassblowing trade. Before Murano became the glassmaking center of the world, the majority of Italian glassmaking took place in Venice. But by 1291, the frequency of furnace fires prompted city officials to enforce the concentration of glassmaking on the island of Murano instead, which was annexed as a part of Venice upon the declaration of this decision. Not only did this isolate the fires, but it also enabled Venetians to isolate and guard its glass production more closely, to ensure that its secrets remained fiercely protected at home. The raw materials that the Murano glassmakers put to use played a large role in setting them apart from their Islamic competition. For instance, access to and utilization of meticulously scrutinized and carefully selected quartz pebbles from the Ticino and Adige river beds rather than just ordinary sand, enabled production of glass called cristallo that expertly mimicked rock crystal in appearance, free of the impurities found in regular sand that often discolored or defected glass, corrupting the clarity needed to achieve that appearance. Possession of the sole trade monopoly on soda ash created by burning Salsola soda and Salsola plants that grew in the Levantine region also provided them with a unique fluxing agent to make melting their glass before molding a smoother and more effective process resulting in fewer impurities and discoloration throughout their glassblowing process. By using only Magnesium from Piemont, they avoided contaminating their products with iron, a major impurity that could impact the ultimate appearance of their masterpieces. Beyond the raw materials they so carefully relied upon, Murano glassmakers also employed superior skill in masterfully blowing, twisting, cutting, and molding their works with masterful hands, into the expertly balanced and proportioned glass works with perfect clarity, symmetry, balance, thickness, and design. By the 14th century, however, another Italian glassmaking center began to surface in Altare – which was not subjected to such rigid restrictions as the industry still flourishing in Venice’s island of Murano. By the 16th century, Altare’s secrets, styles, and techniques had made their way to France and around other European regions. In fact, by 1674, George Ravenscroft, an English glassmaker, was making his own innovations to the industry by patenting a new glass, lead crystal, as a substitute for Venetian crystal. In the 15th century, the Murano glassmakers had begun utilizing quartz sand and potash from sea plants to produce crystal even clearer and purer in appearance than they had before. However, Ravenscroft replaced the potash with higher levels of lead oxide, which produced bright, highly refractive glass that was better suited for cutting and engraving.