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Entry № 294

Nontronite

Iron-rich smectite clay

Ochre clay of quiet transformation.

Chakra

Root · Solar Plexus

Element

Earth

Zodiac

Virgo · Capricorn

Nontronite

I. The Metaphysical Reading

How the stone has been held.

Nontronite is worked with as a stone of slow, patient renewal. Its earthy tone is said to support the humble, unglamorous work of change — decluttering, weeding, digesting — rather than dramatic breakthroughs.

Chakra
Root · Solar Plexus
Element
Earth
Zodiac
Virgo · Capricorn
Keynote
Ochre clay of quiet transformation.

II. The Scientific Reading

What the lattice actually does.

Nontronite is an iron-rich member of the smectite clay group, formed by the weathering and hydrothermal alteration of iron-bearing volcanic rocks. It is named after the town of Nontron in France where it was first described, and it plays a significant role in soil geochemistry and on Mars.

Formula
Na₀.₃Fe₂((Si,Al)₄O₁₀)(OH)₂·nH₂O
System
Monoclinic
Hardness
1.5 – 2.5 (Mohs)
Provenance
France (Nontron), USA, Australia

References & Sources

Independent mineralogical references used to verify the scientific details above.

Mineral Profile

Fact Sheet

Chemical Formula
Na₀.₃Fe₂((Si,Al)₄O₁₀)(OH)₂·nH₂O
Crystal System
Monoclinic
Mohs Hardness
1.5 – 2.5 (Mohs)
Density
2.20 – 2.30 g/cm³
Refractive Index
1.560 – 1.620
Provenance
France (Nontron), USA, Australia
Color Origin
Olive to yellow-green and yellow-brown from iron

Related Crystals

Stones that share this lattice

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Ochre-and-brick banding of the ancient outback.