iron oxide

The red color comes from iron oxide in their mineral structure.

The people may have painted their bodies using red iron oxide.

The yellow that you see in the little holes is an iron oxide.

Rust is a general term for a series of iron oxides.

The active material of the negative plates is iron oxide.

The soil, they believe, contains an iron oxide that often forms in the presence of water.

"Iron oxide has many interesting properties, it turns out," he said.

This allows iron oxides to be used as part of the coloring process.

Duller ones are iron oxide, like you find in soil.

The colour is caused by iron oxides in the rock.