Ochre is a family of natural clay earth pigments, made up of ferric oxide and varying amounts of clay and sand, ranging in colour from yellow to deep orange or brown. The term is also used for the colours produced by this pigment, especially a light brownish-yellow. A variant of ochre containing a large amount of hematite, or dehydrated iron oxide, has a reddish tint known as red ochre. The term "ochre" is colloquially used to cover a range of different substances used for their colours in Aboriginal Australian art and ceremonial decoration, for instance the clay known as "white ochre" or "pipe clay" is derived from kaolin or gypsum.