sedimentary

Moqui Marble

Iron Oxide Concretion (Hematite/Goethite-cemented Sandstone)

AI-generated identification · may be incorrect

Hardness: 5-6 (outer shell), color: brown to reddish-black outer with tan sand core, luster: earthy/metallic, structure: spherical/ovoid, cleavage: none.

Luster: earthy/metallic, structure: spherical/ovoid, cleavage: none

Identified April 2, 2026More sedimentary →

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Physical properties

Hardness: 5-6 (outer shell), color: brown to reddish-black outer with tan sand core, luster: earthy/metallic, structure: spherical/ovoid, cleavage: none.

Formation & geological history

Formed during the Jurassic period (approx. 180 million years ago) via groundwater precipitation of iron minerals around a nucleus (often a sand grain) within Navajo Sandstone layers.

Uses & applications

Primarily collected as geological curiosities, used in spiritual or metaphysical practices (shamans stones), and studied by NASA to understand 'blueberries' on Mars.

Geological facts

Also known as Moqui Balls or Shaman Stones, these are terrestrial analogs to the hematite spherules discovered on Mars by the Opportunity rover. Legend says ancestors' spirits played games with them at night.

Field identification & locations

Identify by their distinct spherical shape, sandpaper-like texture, and heavy weight relative to size. Commonly found in the Navajo Sandstone of southern Utah and northern Arizona.