sedimentary
Moqui Marble (Shaman Stone)
Iron Oxide Concretion (Limonite/Hematite over Sandstone)
Hardness: 5-5.5 (outer shell); Color: Dark brown to black exterior with tan sand interior; Luster: Dull/Metallic; Crystal structure: Amorphous shell; Cleavage: None; Specific gravity: Approx 3.5-4.0.
- Hardness
- 5-5
- Color
- Dark brown to black exterior with tan sand interior
- Luster
- Dull/Metallic
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Physical properties
Hardness: 5-5.5 (outer shell); Color: Dark brown to black exterior with tan sand interior; Luster: Dull/Metallic; Crystal structure: Amorphous shell; Cleavage: None; Specific gravity: Approx 3.5-4.0.
Formation & geological history
Formed in the Navajo Sandstone (Utah/Arizona, USA) during the Jurassic period (approx. 190 million years ago) through the precipitation of iron-rich groundwater around a nucleus.
Uses & applications
Primarily used as a metaphysical or healing stone, collector specimens, and for geological study of diagenetic processes.
Geological facts
Also known as Navajo Cherries; they are protected within Grand Staircase-Escalante National Monument. Similar 'blueberries' were famously found on Mars by the Opportunity rover, suggesting a watery past there.
Field identification & locations
Identify by their spherical or disc-like shape, often found in 'pairs' (male and female textures) weathered out of sandstone cliffs. Common in the American Southwest.
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