Kings International

Details:

• Sienna is a clay containing iron oxide, called limonite, which in its natural state has a yellowish colour. In addition to iron oxide, natural or raw sienna also contains about five percent of manganese oxide, which makes it darker than ochre. When heated, the iron oxide is dehydrated and turns partially to haematite, which gives it a reddish- brown colour. Sienna is lighter in shade than raw umber, which is also clay with iron oxide, but which has a higher content of manganese

Details:Sienna is a clay containing iron oxide, called limonite, which in its natural state has a yellowish colour. In addition to iron oxide, natural or raw sienna also contains about five percent of manganese oxide, which makes it darker than ochre. When heated, the iron oxide is dehydrated and turns partially to haematite, which gives it a reddish- brown colour. Sienna is lighter in shade than raw umber, which is also clay with iron oxide, but which has a higher content of manganese