Wavellite pendant by Lexi Erickson. Photo: Jim Lawson. Originally appeared in Lapidary Journal Jewelry Artist, December 2011. Used by permission of the publisher.
Wavellite is a very attractive mineral, well-known to collectors. Its radial aggregate crystal clusters can be cut into extremely interesting stones.
| Data | Value |
|---|---|
| Name | Wavellite |
| Formula | Al3(OH)3(PO4)2 · 5H2O |
| Etymology | Named after William Wavell (1750-1829), the English physician who discovered the mineral. |
| Occurrence | A secondary mineral in hydrothermal veins; also in aluminous and phosphatic rocks. |
| Colors | White, greenish white, green, yellowish green, yellow, yellow-brown, brown to brownish black. Very rarely colorless, blueish. |
| Fracture | Subconchoidal to uneven |
| Hardness | 3.5-4 |
| Cleavage | Perfect 1 direction |
| Crystallography | Orthorhombic. Crystals very tiny; usually as radial aggregates of acicular crystals; often spherical crystal clusters; crusts; stalactitic. |
| Crystallographic Forms | |
| Refractive Index | 1.520-1.561 |
| Birefringence | 0.025 |
| Luminescence | Occasionally blueish in LW (various localities). |
| Luminescence Present | Yes |
| Luminescence Type | Fluorescent, UV-Long |
| Absorption Spectrum | Not diagnostic |
| Pleochroism | Weak: Greenish/Yellowish. |
| Optics | a = 1.520-1.535; β = 1.526-1.543; γ =1.545-1.561. Biaxial (+), 2V= 71°. |
| Optic Sign | Biaxial + |
| Luster | Vitreous; also resinous to pearly. |
| Specific Gravity | 2.36 |
| Transparency | Translucent. |
A cluster of spherical wavellites, 6.0 x 5.5 x 3.9 cm, Saline Co., Arkansas, USA. © Rob Lavinsky, www.iRocks.com. Used with permission.
Since wavellite’s radiating crystal clusters can splinter, they make it a very difficult gem to cut. The individual crystals in the clusters are very small. Gem cutters can fashion cabochons as well as freeform shapes from this material. However, any faceted gems would be a tremendous rarity.
This striking specimen displays massed, acicular (needle-like) wavellite crystals radiating from the center of the stone. You can also see how one “ball” of wavellite grew around another. 3.4 x 2.0 x 1.1 cm, Avant Mine, Avant, Garland Co., Arkansas, USA. © Rob Lavinsky, www.iRocks.com. Used with permission.
No known synthetics or enhancements.
Hot Springs, Arkansas produces wavellites in fine, spherical and radial groups of acicular crystals.
The type locality, High Down Quarry, Devon, England, also produces excellent specimens.
Other gem-quality sources include the following:
Wavellites, 10.1 x 5.5 x 5.8 cm, Avant Mine, Garland County, Arkansas, USA. © Rob Lavinsky, www.iRocks.com. Used with permission.
Lapidaries can cut cabochons up to several inches in length from Arkansas material. No faceted gems have been reported, yet.
Wavellite has a relatively low hardness (3.5 to 4) and perfect cleavage, so gems for jewelry pieces such as rings need protective settings. Pendants and earrings would make excellent choices for this material. However, you’re more likely to encounter these stones in gem collections than jewelry collections.
Store these gems separately from other harder stones to avoid contact scratches. For cleaning, use a soft brush, mild detergent, and warm water. Consult our gemstone jewelry cleaning guide for more recommendations.
Wavellite specimen, collected by G. M. Baker, 1984, from Chester County, Pennsylvania. Mineral collection of Brigham Young University, Department of Geology, Provo, Utah. Photo by Andrew Silver. Public Domain.
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