Watercolor Dirtbag
This mix is made from PR209, PO48, and PY150. In other words, Quin Coral, Quin Burnt Orange, and Nickel Azo Yellow. Another way to mix is this is with Quin Coral and Quin Gold, since Quin Gold is itself a mix of Quin Burnt Orange and Nickel Azo Yellow.
Burnt Sienna is one of the most classic earth tones, an earth orange that ranges from an orangey brown through to a peachy gold. It is often used to mix up a range of browns and to neutralize blues, which are its opposite.
Burnt Sienna is just one of many earth tones that are traditionally made with PBr7 (Pigment Brown #7); others include Raw Sienna, Raw Umber, and Burnt Umber. So basically all of them. PBr7 colors vary quite a bit in granulation depending on who you get them from. Holbein’s earth tones, like this one, tend to be quite creamy and smooth without granulation.