Ceramic flux in the context of Strontium

A slip is a clay slurry used to produce pottery and other ceramic wares. Liquified clay, in which there is no fixed ratio of water and clay, is called slip or clay slurry which is used either for joining leather-hard (semi-hardened) clay body (pieces of pottery) together by slipcasting with mould, glazing or decorating the pottery by painting or dipping the pottery with slip. Pottery on which slip has been applied either for glazing or decoration is called slipware.

Engobe, from the French word for slip, is a related term for a liquid suspension of clays and flux, in addition to fillers and other materials. This is in contrast to slips, which are historically considered to be a liquid suspension of only clay or clays in water.

Lead-glazed earthenware is one of the traditional types of earthenware with a ceramic glaze, which coats the ceramic bisque body and renders it impervious to liquids, as terracotta itself is not. Plain lead glaze is shiny and transparent after firing. Coloured lead glazes are shiny and either translucent or opaque after firing. Three other traditional techniques are tin-glazed (in fact this is lead glaze with a small amount of tin added), which coats the ware with an opaque white glaze suited for overglaze brush-painted colored enamel designs; salt glaze pottery, also often stoneware; and the feldspathic glazes of Asian porcelain. Modern materials technology has invented new glazes that do not fall into these traditional categories.

In lead glazes, tints provided by impurities render greenish to brownish casts, with aesthetic possibilities that are not easily controlled in the kiln. The Romans used lead glazes for high-quality oil lamps and drinking cups. At the same time in China, green-glazed pottery dating back to the Han period (25–220 AD) gave rise eventually to the sancai ('three-color') Tang dynasty ceramics, where the white clay body was coated with coloured glazes and fired at a temperature of 800 degrees C. Lead oxide was the principal flux in the glaze. Polychrome effects (i.e. the colours) were obtained by using the oxides of copper (which turns green), iron (brownish yellow), and less often manganese (brown) and cobalt (blue).

Green-glazed pottery (Chinese: 緑釉陶器) was a type of colored pottery developed in China during the Eastern Han period (25–220 CE). The body of green-glazed pottery ceramics was made of clay, coated with a layer of glaze, and fired at a temperature of 800 degrees Celsius. Green-glazed pottery is a type of lead-glazed earthenware (Chinese: 鉛釉陶器): lead oxide was the principal flux in the glaze, often mixed with quartz in the proportion of 3:1. The polychrome effect was obtained by using as coloring agent copper (which turns green).

Due to the low firing temperature, the bodies are earthenware, and the glaze often only applied to parts of the objects, which are fragile and have high water absorption. In some cases the lead glazes make the objects slightly poisonous. For these reasons, the objects are only known as grave goods from burials, and examples used in everyday life have not been found. In surviving examples the glaze has often corroded, and turned a "greyish-silver". They are liable to flake off.

Boron trioxide or diboron trioxide is the oxide of boron with the formula B₂O₃. It is a colorless transparent solid, almost always glassy (amorphous), which can be crystallized only with great difficulty. It is also called boric oxide or boria. It has many important industrial applications, chiefly in ceramics as a flux for glazes and enamels and in the production of glasses.