Sienna is the color of Italian dirt. It’s named after Sienna, Italy, where Renaissance painters first got the earthy pigment. It ranges from the yellowish raw sienna like sand, or the darker brownish red of burnt sienna.
You can draw a sienna cow with a reddish-brown crayon, or describe your grandparents' carpet as sienna. Artists also use sienna for the natural pigment that contains iron oxide. Sienna is yellowish-brown, and it takes on a darker, redder tint when it's heated. It's a common pigment in oil paints and has been used since the sixteenth century, when it was produced in the Italian city of Sienna.