Art and Design
The pigment sienna was known and used, in its natural form, by the ancient Romans. It was mined near Arcidosso, formerly under Sienese control, now in the province of Grosseto, on Monte Amiata in southern Tuscany. It was called terra rossa (red earth), terra gialla, or terra di Siena. During the Renaissance, it was noted by the most widely read author about painting techniques, Giorgio Vasari, under the name terra rossa. It became, along with umber and yellow ochre, one of the standard browns used by artists from the 16th to 19th centuries, including Caravaggio (1571-1610) and Rembrandt (1606-1669), who used all the earth colours, including ochre, sienna and umber, in his palette
Sienna (from Italian: terra di Siena, "Siena earth") is an earth pigment containing iron oxide and manganese oxide. In its natural state, it is yellow-brown and is called raw sienna. When heated, it becomes a reddish brown and is called burnt sienna. It takes its name from the city-state of Siena, where it was produced during the Renaissance.