sedimentary

Moqui Marble (Concretion)

Iron oxide concretion (Goethite/Hematite and Sandstone)

AI-generated identification · may be incorrect

Hardness: 5-5.5 (outer shell); Color: Rusty brown, reddish, or tan; Luster: Dull, earthy; Crystal structure: Amorphous/Microcrystalline; Specific Gravity: varies (usually 2.5-3.5)

Hardness: 5-5
Color: Rusty brown, reddish, or tan
Luster: Dull, earthy

Identified April 11, 2026More sedimentary →

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Physical properties

Hardness: 5-5.5 (outer shell); Color: Rusty brown, reddish, or tan; Luster: Dull, earthy; Crystal structure: Amorphous/Microcrystalline; Specific Gravity: varies (usually 2.5-3.5)

Formation & geological history

Formed by the precipitation of iron-rich minerals from groundwater in Navajo Sandstone systems. Most are of late Cenozoic age (approx. 2 million years old) but formed within rocks of the Jurassic period.

Uses & applications

Primarily used as metaphysical stones, educational specimens for geologists, and decorative collector pieces.

Geological facts

Also known as Moqui Balls or Shaman Stones, these spherical formations are found primarily in the Southwestern United States. Scientists have studied them as terrestrial analogs for the 'blueberries' discovered on Mars by the Opportunity rover.

Field identification & locations

Identify by their distinct spherical or disk-like shape and iron-rich crust. Usually found within sandstone layers or weathered out onto the canyon floor. Common in southern Utah.