Red earth pigment is a term commonly used to describe the color of pigments derived from natural red clay deposits. This pigment is characterized by its deep, rusty red color and is often used in various fields, including art, pottery, and construction. However, several synonyms exist for this earth pigment, including red ochre, terra rossa, and sienna. Red ochre is a reddish-brown pigment that is composed of iron oxide and clay and is commonly found in ancient cave paintings. Terra rossa is a bright red clay soil found primarily in Mediterranean regions. Sienna, on the other hand, is a brownish-red earth pigment that comes from Siena, Tuscany, Italy.