Natural clays like terracotta; more fragile and fired at low temperatures

• A. Stoneware
• B. Kaolin
• C. Earthenware
• D. Porcelain

Answer: (C)

Firing temperature shapes how much a clay body vitrifies, which in turn affects strength and porosity. Earthenware is made from natural clays like terracotta and is fired at relatively low temperatures, so it remains porous and more fragile than higher-fired ceramics. The reddish color of terracotta often comes from iron oxide in the clay. Because it doesn’t vitrify fully, earthenware is softer and chips more easily unless it is glazed to seal the surface.

Stoneware, by contrast, is fired much hotter and becomes vitrified, making it non-porous and durable. Kaolin is the white clay mineral used to make porcelain, which requires high-temperature firing to develop strength and translucency. Porcelain itself is a high-fired, dense ceramic that resists chipping more than earthenware but is not the same low-fired, fragile terracotta body.