Green Prehnite Cabochon
ORTHORHOMBIC

Prehnite

Ca2Al2Si3O12(OH)

Hardness
6–6.5
Refractive Index
1.61–1.64
Spec. Gravity
2.8–3.0
System
Orthorhombic
View Mineral
Prehnite gemstones are usually light green in color, with a whitish hue or yellowish tinge. Deep green gemstones are not common. Prehnite gemstones often appear cloudy or velvety, and rarely fully transparent. They may also contain colors zones of lighter and darker green.

About

Prehnite has always been a minor collectors gemstone, but relatively recent deposits discovered in Africa containing facetable Prehnite in large quantities has made this gemstone more available and popular.  Prehnite is very sensitive to heat and has perfect easily chips, so care must be exercised when cutting. Prehnite Cat's Eyes do exist from the Australian finds, but these are very rare.

Uses

Prehnite is an inexpensive gemstone, and due its lack of full transparency it is usually cut into cabochons and beads. Other facets may be cut, but less commonly. Prehnite may also be carved into small ornamental objects such as flowers.

Treatments & Enhancements

Prehnite gemstones are natural and not heated or artificially enhanced.

Sources

Prehnite sources include Mali, South Africa, Namibia, Australia, China, and the U.S. (New Jersey).

Similar Gemstones

Further Reading

In the Rough