sedimentary

Moqui Marble (Iron Oxide Concretion)

Iron Oxide Concretion (primarily Limonite/Hematite around a Sandstone center)

AI-generated identification · may be incorrect

Hardness: 5-6 (outer shell); Color: Dark brown to black outer, tan sand interior; Luster: Dull or sub-metallic; Structure: Spherical to ellipsoidal; Specific Gravity: 2.5-4.5.

Hardness: 5-6 (outer shell)
Color: Dark brown to black outer, tan sand interior
Luster: Dull or sub-metallic

Identified May 25, 2026More sedimentary →

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Physical properties

Hardness: 5-6 (outer shell); Color: Dark brown to black outer, tan sand interior; Luster: Dull or sub-metallic; Structure: Spherical to ellipsoidal; Specific Gravity: 2.5-4.5.

Formation & geological history

Formed in the Jurassic-era Navajo Sandstone (approx. 180 million years ago) through groundwater precipitation of iron-bearing minerals around a nucleus (like a small pebble or fossil) in porous rock.

Uses & applications

Primarily used for geological education, rock collecting, and as metaphysical stones (often called shaman stones).

Geological facts

Also known as Moqui Balls or Shaman Stones, these concretions are protected and illegal to collect within National Parks like Zion. They are viewed as sacred by some Native American tribes.