Guy Lacroix
The Rainbow of Rocks, South Coyote Buttes
"Blood of the Living Rocks
What colors the sandstone red? The red color is caused by a union of iron and oxygen (an iron oxide) known as hematite (Fe 2 O ), a mineral named from the Greek word for blood. Iron is a powerful pigment present in many sediments and rocks, thus it commonly imparts color to the rocks.
Although red is the common pigment color, not all iron oxides are red; some are brown or yellow (minerals - limonite or goethite), and some are black (mineral - magnetite). Some iron minerals are metallic yellow (mineral - pyrite consisting of iron sulfide) or green (minerals - chlorite or clay consisting of iron silicate)."
Rainbow of Rocks
Mysteries of Sandstone Colors and Concretions
in Colorado Plateau Canyon Country
by Marjorie A. Chan and William T. Parry
Dept. of Geology and Geophysics
The Rainbow of Rocks, South Coyote Buttes
"Blood of the Living Rocks
What colors the sandstone red? The red color is caused by a union of iron and oxygen (an iron oxide) known as hematite (Fe 2 O ), a mineral named from the Greek word for blood. Iron is a powerful pigment present in many sediments and rocks, thus it commonly imparts color to the rocks.
Although red is the common pigment color, not all iron oxides are red; some are brown or yellow (minerals - limonite or goethite), and some are black (mineral - magnetite). Some iron minerals are metallic yellow (mineral - pyrite consisting of iron sulfide) or green (minerals - chlorite or clay consisting of iron silicate)."
Rainbow of Rocks
Mysteries of Sandstone Colors and Concretions
in Colorado Plateau Canyon Country
by Marjorie A. Chan and William T. Parry
Dept. of Geology and Geophysics