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 |
| Colors | White, greenish white, green, yellowish green, yellow, yellow-brown, brown to brownish black. Very rarely colorless, blueish. |
| Crystallography | Orthorhombic. Crystals very tiny; usually as radial aggregates of acicular crystals; often spherical crystal clusters; crusts; stalactitic. |
| Refractive Index | 1.520-1.561 |
| Luster | Vitreous: also resinous to pearly. |
| Hardness | 3.5-4 |
| Fracture | Subconchoidal to uneven |
| Specific Gravity | 2.36 |
| Birefringence | 0.025 |
| Cleavage | Perfect 1 direction |
| Luminescence | Occasionally bluish in LW (various localities). |
| Luminescence Present | Yes |
| Luminescence Type | Fluorescent, UV-Long |
| Transparency | Translucent. |
| Absorption Spectrum | Not diagnostic. |
| Formula |
Al3(OH)3(PO4)2 · 5H2O. |
| 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 + |
| 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. |
“Wavellite,” 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,” crystals radiating from the center of the stone. You can also see how one “ball” of wavellite grew around another. “Wavellite,” 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:
“Wavellite,” 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. Thus, 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 – USGS Mineral Specimens 1184,” collected by G. M. Baker, 1984, from Chester County, Pennsylvania. Mineral collection of Brigham Young University, Department of Geology, Provo, Utah by Andrew Silver. Public Domain.
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