4. Silicate ceramics with vitrified paste, vitréous and porcelain

4.1 Classification

Porcelain is a dense, white, relatively translucent ceramic material.

The average composition of porcelain bodies is in the ternary system kaolin – feldspar – quartz, although it is necessary to make a classification according to the firing temperature:

• Products fired between 1,380 and 1,420°C are called "hard porcelain";

• products fired between 1,200 and 1,300°C are vitréous, culinary porcelain (tableware), sanitary porcelain or vitréous (sanitary products), electrotechnical porcelain (electrical insulators) or porcellanatos (floor tiles). The term "stoneware porcelain" is also used.

The main difference between these products...