Entry № 291
Neptunite
Alkali titanosilicate
Black prisms from the god of the sea.
Chakra
Root · Third Eye
Element
Water · Earth
Zodiac
Scorpio · Pisces

I. The Metaphysical Reading
How the stone has been held.
Neptunite is held as a stone of protection and deep discernment. Its glossy black prisms are said to help sift subconscious material — the parts of a decision usually left unexamined — before bringing them into the light.
- Chakra
- Root · Third Eye
- Element
- Water · Earth
- Zodiac
- Scorpio · Pisces
- Keynote
- Black prisms from the god of the sea.
II. The Scientific Reading
What the lattice actually does.
Neptunite is a rare alkali titanosilicate mineral, best known from the Benitoite Gem Mine in San Benito County, California, where it occurs as glossy black prisms on white natrolite alongside the blue mineral benitoite. It forms in hydrothermally altered blueschist.
- Formula
- KNa₂Li(Fe²⁺,Mn²⁺)₂Ti₂Si₈O₂₄
- System
- Monoclinic
- Hardness
- 5 – 6 (Mohs)
- Provenance
- USA (California — Benitoite Gem Mine), Greenland
References & Sources
Independent mineralogical references used to verify the scientific details above.
Mineral Profile
Fact Sheet
- Chemical Formula
- KNa₂Li(Fe²⁺,Mn²⁺)₂Ti₂Si₈O₂₄
- Crystal System
- Monoclinic
- Mohs Hardness
- 5 – 6 (Mohs)
- Density
- 3.19 – 3.23 g/cm³
- Refractive Index
- 1.690 – 1.740
- Provenance
- USA (California — Benitoite Gem Mine), Greenland
- Color Origin
- Deep black to reddish-black, opaque
Related Crystals
Stones that share this lattice
Next in the Atlas
Nevada Rose
A desert stone flowering in pink.




