Wavellite is a mineral with the chemical formula Al₃(PO₄)₂(OH, F)₃·5H₂O. Wavellite is an aluminum basic phosphate, and is typically green, yellow, or brown in color. Wavellite is a relatively soft mineral, with a hardness of 3.5 to 4 on the Mohs scale. It has a perfect cleavage, which means that it can be split into thin, even sheets.
Wavellite is a beautiful green mineral that is often found in radiating clusters. Wavellite is a very attractive mineral, well-known to collectors. Its radial aggregate crystal clusters can be cut into extremely interesting stones.
Wavellite exhibits different shades of green, which range from dark emerald green, apple green, bright green, to pale green.
Wavellite usually occurs in globular or hemispherical aggregates of botryoidal crusts on matrix, radiating crystals, or stalactitic deposits.
|Green Radial Wavellite. From Mauldin Mt., Montgomery Co., Arkansas, USA|
Photo Credit: Andreas Schmid
Wavellite was first described in 1805 for an occurrence at High Down, Filleigh, Devon, England and named by William Babington in 1805 in honor of Dr. William Wavell (1750–1829), a Devon-based physician, botanist, historian, and naturalist, who brought the mineral to the attention of fellow mineralogists.
Wavellite is a secondary mineral, meaning that it forms from the alteration of other minerals. It is most commonly found in aluminous, low-grade metamorphic rocks, in phosphate and limonitic deposits; more rarely as a late-forming hydrothermal vein mineral.
When broken across the spheres, wavellite exhibits a radial crystalline structure - the local old timers call it "cats-eye". Color may vary from light to dark green at this locale, the intensity of the color is due to how much vanadium is present in the structure of the mineral.
Properties of Wavellite
- Formula: Al₃(PO₄)₂(OH, F)₃·5H₂O
- System: Orthorhombic
- Colour: Green to yellowish-green ...
- Lustre: Vitreous, Greasy, Pearly
- Hardness: 3½ - 4
- Crystal habit: Spherical, radial aggregates; striated prisms; crusty to stalactitic
- Streak is white.
- Associated Minerals are quartz, micas, turquoise and limonite.
- Other Characteristics: surface of globules often have minute crystals giving off tiny sparkles.
- Notable Occurances include Arkansas and Pennsylvania, USA; Bolivia and England.
- Best Field Indicators are crystal habit, green color and softness.
Wavellite is a relatively rare mineral, but it has a few different uses. It is sometimes used as a gemstone, and it is also used as a source of aluminum. Wavellite is also used in some industrial applications, such as in the manufacture of paints and pigments.
|Polished Wavellite cabochon, from Arkansas.
Photo: James Carpenter
Where to Find Wavellite
It occurs in association with crandallite and variscite in fractures in aluminous metamorphic rock, in hydrothermal regions and in phosphate rock deposits. It is found in a wide variety of locations notably in the Mount Ida, Arkansas area in the Ouachita Mountains.
Wavellite is found in a variety of locations around the world, including:
- Arkansas, United States: Wavellite is found in the Ouachita Mountains of Arkansas, particularly in the Mount Ida area. This is the most famous locality for wavellite, and some of the finest specimens in the world have been found here.
- Brazil: Wavellite is found in a number of locations in Brazil, including the states of Minas Gerais, Bahia, and Rio Grande do Sul. Some of the most beautiful wavellite specimens in the world come from Brazil.
- China: Wavellite is found in a number of locations in China, including the provinces of Hunan, Jiangxi, and Anhui.
- Germany: Wavellite is found in a number of locations in Germany, including the states of Saxony, Thuringia, and Bavaria.
- India: Wavellite is found in a number of locations in India, including the states of Rajasthan, Madhya Pradesh, and Andhra Pradesh.
- Madagascar: Wavellite is found in a number of locations in Madagascar, including the regions of Ihorombe and Anosy.
- Morocco: Wavellite is found in a number of locations in Morocco, including the regions of Ouarzazate and Errachidia.
- Russia: Wavellite is found in a number of locations in Russia, including the Ural Mountains and the Kola Peninsula.
- South Africa: Wavellite is found in a number of locations in South Africa, including the provinces of KwaZulu-Natal and Limpopo. Africa
How to Care for Wavellite
Wavellite is a relatively soft mineral, so it should be handled with care. It should be stored in a cool, dry place. Wavellite can be cleaned with a soft brush and mild soap and water.See Also:
Where to Find Sunstone in Oregon?
Different Types and Colours of Moonstone
What Is Pseudomorph Mineral?