The main components of colored glass are purified quartz sand and potassium feldspar, albite, lead oxide (the basic component of glass), saltpeter (potassium nitrate: KNO3; cooling), alkali metals, alkaline earth metals (magnesium chloride: MgCl, melting aid, increasing durability), aluminum oxide (increasing brightness and chemical durability) Chromogenic agents of various colors (such as yellow green of iron oxide, blue green of copper oxide, etc.) and clarifying agents (white arsenic, antimony trioxide, nitrate, sulfate, fluoride, chloride, cerium oxide, ammonium salt, etc.). Crystal glass is melted at a high temperature of 1450 ° C, and glass artworks are produced at a low temperature of 850 ° C ~ 900 ° C through the fine process of dewaxing and color mixing casting. In English, glass containing lead compounds is generally called crystal or crystal glass because of its transmittance and clarity, which are similar to natural crystals. In China, it is called glass. As a kind of colored crystal glass, the proportion of lead compounds added to colored glass (makes the glass products have high refractive index and look transparent and bright. At present, most of the products used for casting contain more than 24%). The definitions vary from country to country, such as 10% in the European Union and 24% ~ 40% in the Czech Republic. Generally speaking, when the proportion of lead oxide reaches more than 24%, the glass has good transmittance and refractive index, and is also heavier and softer.
The confusion of the names of colored glass and its related derivatives in history has led to the misunderstanding and misunderstanding of colored glass. “Glazed tile” and modern “Boshan made colored glass” are the most demonstrable examples.
Post time: Sep-13-2022