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Entry № 194

Fossil Shell Jasper

Turritella Agate

Chalcedony that swallowed a shoreline.

Chakra

Root · Sacral

Element

Earth · Water

Zodiac

Cancer · Capricorn

Fossil Shell Jasper

I. The Metaphysical Reading

How the stone has been held.

Fossil shell jasper is worked with as a stone of ancestral time, kept nearby during genealogy, grief tending and any practice that asks a person to hold the past in cupped hands. Practitioners hold it as a reminder that a life can be recorded as clearly as a signature.

Chakra
Root · Sacral
Element
Earth · Water
Zodiac
Cancer · Capricorn
Keynote
Chalcedony that swallowed a shoreline.

II. The Scientific Reading

What the lattice actually does.

Fossil shell jasper — traditionally sold as turritella agate — is a Wyoming freshwater chalcedony from the Eocene Green River Formation in which dense populations of high-spired snail shells (properly Elimia tenera, misidentified for a century as Turritella) have been silicified and preserved in cross-section within a brown chalcedonic matrix.

Formula
SiO₂ chalcedony replacing CaCO₃ shells
System
Trigonal (microcrystalline)
Hardness
6.5 – 7 (Mohs)
Provenance
USA (Wyoming — Green River Formation), Indonesia

References & Sources

Independent mineralogical references used to verify the scientific details above.

Mineral Profile

Fact Sheet

Chemical Formula
SiO₂ chalcedony replacing CaCO₃ shells
Crystal System
Trigonal (microcrystalline)
Mohs Hardness
6.5 – 7 (Mohs)
Density
2.58 – 2.64 g/cm³
Refractive Index
1.530 – 1.540
Provenance
USA (Wyoming — Green River Formation), Indonesia
Color Origin
Warm brown to honey chalcedony packed with pale cross-sectioned spiral shells

Related Crystals

Stones that share this lattice

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Franklinite

A black spinel from the strangest orebody in America.