Investigating the Effects of Silica (SiO2) on the Structure of Glazes

Glaze is a layer of glossy or matte glass that is applied to the surface of pottery, which not only enhances its beauty but also provides strength and impermeability to the surface. Glazes are divided into several categories according to the type of ingredients as well as the temperature and type of firing. Glazes made from silica are transparent and colorless, which metal oxides such as copper oxide or cobalt, etc. are added to color the glaze. In the primary division, the opaqueness or transparency of the glaze is relevant, which depends on the lead or alkalinity of the glaze. Other classifications of glaze are based on the type of materials used and the firing temperature as well as the firing environment of the glaze. Knowing the types of materials used in the glazes significantly aids in better examination and identification, as well as in recognizing existing defects in the glaze, the type of damage, and the preservation of historical objects. One of the materials used in the structure of historical glazes is silica or flint, which is also used in modern glazes. This substance exists in nature in the form of quartz stones, of which different types have been identified in different parts of the world, plays an important role in the glaze structure. It enhances the bonding between the body and the glaze, and when combined with other materials, it makes the glaze glassy. It plays an important role in the strength of the glaze, and therefore its existence is necessary in the glaze, especially at high temperatures. This research aims to study the physical and chemical structure of silica and its role and importance in glaze formulation. To achieve this, it is necessary first to examine the type and structure of silica, and then discuss its advantages and disadvantages in the structure of the glaze and its importance in the glaze. By studying books and articles this research tries to familiarize the audience with one of the most basic materials used in glaze, which is silica, and how the quantity and type of silica used affects the type of glaze produced.