Ferric oxide in the context of "Hematite"

Ochre (/ˈoʊkər/ OH-kər; from Ancient Greek ὤχρα (ṓkhra), from ὠχρός (ōkhrós) 'pale'), iron ochre, sometimes ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the colours produced by this pigment, especially a light brownish-yellow. A variant of ochre containing a large amount of hematite, or dehydrated iron oxide, has a reddish tint known as red ochre (or, in some dialects, ruddle).

Ochre is also clays coloured with iron oxide derived during the extraction of tin and copper.

The Nazca lines (/ˈnɑːzkə/, /-kɑː/) are a group of over 700 geoglyphs made in the soil of the Nazca Desert in southern Peru. They were created between 500 BC and 500 AD by people making depressions or shallow incisions in the desert floor, removing pebbles and leaving different-colored dirt exposed. There are two major phases of the Nazca lines, Paracas phase, from 400 to 200 BC, and Nazca phase, from 200 BC to 500 AD. In the 21st century, several hundred new figures had been found with the use of drones, and archaeologists believe that there are more to be found.

Most lines run straight across the landscape, but there are also figurative designs of animals and plants. The combined length of all the lines is more than 1,300 km (800 mi), and the group covers an area of about 50 km (19 sq mi). The lines are typically 10 to 15 cm (4–6 in) deep. They were made by removing the top layer of reddish-brown ferric oxide–coated pebbles to reveal a yellow-grey subsoil. The width of the lines varies considerably, but more than half are slightly more than 33 cm (13 in) wide. In some places they may be only 30 cm (12 in) wide, and in others reach 1.8 m (6 ft) wide.

Red beds (or redbeds) are sedimentary rocks, typically consisting of sandstone, siltstone, and shale, that are predominantly red in color due to the presence of ferric oxides. Frequently, these red-colored sedimentary strata locally contain thin beds of conglomerate, marl, limestone, or some combination of these sedimentary rocks. The ferric oxides, which are responsible for the red color of red beds, typically occur as a coating on the grains of sediments comprising red beds. Classic examples of red beds are the Permian and Triassic strata of the western United States and the Devonian Old Red Sandstone facies of Europe.