Murano glass is created only on the island of Murano, located within the borders of the city of Venice in Northern Italy. Murano glass in its core is a material consisting of a homogenous mixture of various substances in the form of a powder. The glass powder transforms into a pasty consistency when heated to a temperature varying between 1300°C and 1400°C and becomes workable liquid glass at around 1500°C. Gold or silver foil are often added to the glass mixture, along with such minerals as copper for sparkles, zinc for white color, cobalt for blue, manganese for violet, and so on. The mixture is then mouth-blown and/or hand-crafted by master glassmakers using special techniques and basic tools, many of which have been developed in the Middle Ages and changed little since then.