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Crystal glass is a type of glass which contains considerable amount of lead-oxide PbO or barium oxide BaO.

Lead-oxide component increases the glass refraction index and light dispersion in it (from a jewelry point of view – “change of colours”, “fire”). Barium oxide component increases only the refraction index.

The crystal glass faceting similarly to precious stones faceting allows crystal glass full showing its features, which are the results of big refraction index and dispersion. The name was given due to its likeness with rock crystal. It is produced by alloying lead-oxide PbO with silicon dioxide, combination of natrum and kalium (soda salt and potash) and small addition of other oxides. Big content of PbO increases the refraction and dispersion indexes – two indexes which are very important in some optical applications. These characteristics add sparkling and shining to the glass, which decorates the finest articles of tableware and works of art.

Crystal glass is a lead-silicate glass, containing 13-30 % and more lead-oxides and up to 17 % of potassium oxides. High-quality tableware and decorative articles are made from crystal glass. It has a higher weight, transparence, refraction and gloss, but less thermal resistance in comparison with other types of glass. Due to a lead content and specific grading of angles, formed by facets, crystal articles differ in bright multicolor change. They sound pretty. Methods of articles decoration: engraving, faceting, carving, grinding work.

Lead-oxide addition to glass mass was practiced at the very beginning of glass production in Ancient Egypt and Mesopotamia. Nevertheless crystal glass in more or less present-day form was obtained only in 1676 by English master George Ravenscroft.