sienna n : an earth color containing ferric oxides; used as a pigment

see Sienna

English

Etymology

From terra di Sienna, "earth of Siena", Siena being the most notable Renaissance location of the clay

Pronunciation

• sē-ĕnʹə, /siˈɛnə/, /si"En@/

Homophones

• Siena

Noun

1. a form of clay containing iron and manganese.
2. a pigment with a reddish-brown colour.
3. a reddish-brown colour.

   sienna colour:   

Synonyms

• (clay): raw sienna

Derived terms

• burnt sienna
• raw sienna

Translations

Adjective

sienna

1. having a reddish-brown colour.

Translations

Anagrams

• insane

For the Italian city see Siena.

Sienna is a form of limonite clay most famous in the production of oil paint pigments. Its yellow-brown colour comes from ferric oxides contained within. As a natural pigment, it (along with its chemical cousins ochre and umber) was one of the first pigments to be used by humans, and is found in many cave paintings.

Sienna, in and of itself, is sometimes referred to as "raw sienna", in order to differentiate it from "burnt sienna", which is a more common pigment than the raw form. The difference is in the process applied to burnt sienna, which is raw sienna heated to remove the water from the clay and redden its brownish colour.

The name derives from the most notable Renaissance location for the earth, Siena, Italy, and is short for terra di Siena, "earth of Siena". The mines used to produce this sienna petered out in the 1940s. Much of today's sienna production is still carried out in the Italian islands of Sardinia and Sicily, while other major deposits are found in the Appalachian Mountains, where it often goes hand-in-hand with the region's iron deposits.

Many of these deposits date back to the Precambrian, and are pointed to as evidence of the Snowball Earth hypothesis.

See also

• clay earth pigment