Ceramic glaze

Ceramic glaze is an impervious layer or coating of a vitreous substance which has been fused to a ceramic body through firing. Glaze can serve to color, decorate or waterproof an item.

Use

Glazing renders earthenware vessels suitable for holding liquids, sealing the inherent porosity of terracotta. Glaze is also used on stoneware and porcelain. In addition to their functional aspect, glazes can form a variety of surface finishes, including degrees of glossy or matte finish and color. Glazes may also enhance the underlying design or texture either unmodified or inscribed, carved or painted.

Glaze is used to weatherproof brick or tile building materials. The Iron Pagoda, built in 1049 in Kaifeng, China, of glazed bricks is an example.

Composition

Raw materials of ceramic glazes generally include silica, which will be the main glass former. Various metal oxides, such as sodium, potassium and calcium, act as a flux to lower the melting temperature. Alumina, often derived from clay, stiffens the molten glaze to prevent it from running off the piece. Colorants, such as iron oxide, copper carbonate or cobalt carbonate, and sometimes opacifiers such as tin oxide or zirconium oxide, are used to modify the visual appearance of the fired glaze. Glaze for lead-glazed earthenware is transparent and glossy after firing.

Glaze

Glaze or glazing may refer to:

See also

Glaze (surname)

Glaze is a surname. Notable people with the surname include:

Glaze (cooking technique)

A glaze in cooking is a coating of a glossy, often sweet, sometimes savoury, substance applied to food typically by dipping, dripping, or with a brush. Egg whites and basic icings are both used as glazes. They often incorporate butter, sugar, milk, and certain oils. For example, doughnut glaze is made from a simple mixture of powdered or confectioner's sugar and water that the doughnuts are dipped in, or some pastry doughs have a brushed on coating of egg whites. Glazes can also be made from fruit or fruit juice along with other ingredients and are often applied to pastries. A type of savory glaze can be made from reduced stock that is put on meat or vegetables. Some candies or confections may be coated in edible wax glazes.

History

A typical medieval English glaze was the 'Elizabethan' glaze made from lightly beaten egg white and sugar used predominantly on pastries of the time.

See also