Ca₂Al(AlSi₃O₁₀)(OH)₂
Prehnite
Often called the first mineral named for a person, a pale-green silicate from the Cape, described in 1788.
- Formula
- Ca₂Al(AlSi₃O₁₀)(OH)₂
- Mohs hardness
- 6–6.5
- Crystal system
- orthorhombic
- Colour
- green
- Element
- earth
- Chakra (tradition)
- heart
- Zodiac
- Libra, Virgo
- Month
- —
- Where the earth keeps it
- South Africa, Australia
What it actually is
Prehnite is Ca₂Al(AlSi₃O₁₀)(OH)₂ before it is a story. The lattice is orthorhombic, Mohs 6–6.5, and the eye meets green.
The better pieces still come out of the ground in South Africa, Australia. Often called the first mineral named for a person, a pale-green silicate from the Cape, described in 1788.
What the old tradition whispers
The parlour tradition ties Prehnite to earth and to the heart centre. The old site stood it near: Libra, Virgo.
How not to turn it to ash
A hard stone survives a daily ring, yet two diamonds in one box will scratch each other. Warm water and a soft cloth are enough.