Home > Laskowski Ⅱ – June 29 > MS1842 Fluorwavellite (IMA2015-077) found 2001

Fluorwavellite (IMA2015-077) found 2001 - Sold


Fluorwavellite is a partially fluorinated hydrous aluminum phosphate. The story of fluorwavellite began in the late 18th century with the discovery of wavellite; Davy (1805) named wavellite after its discoverer, Dr. Wavel [sic] (1750-1829). Nominally, wavellite is a fluorine-free hydrous aluminum phosphate with three hydroxyl groups (OH-) per formula unit. By the late 19th century, mineralogists noted minor fluorine in some wavellite samples. Crystal structure refinement by Kampf et al. (2017) showed that fluorine replaces one of three hydroxyl groups per formula unit, qualifying the mineral for species status. The name fluorwavellite recognizes its essential fluorine content and structural relationship with long established species wavellite.

Radiating fluorwavellite groups, to 7 mm across, scatter over a quartz encrusted surface. Associated are later elongate gray microcrystals of selenium and earlier minute (<0.5 mm) white spheres of crandallite. The matrix is an impure limestone; backside of the specimen has been sawn. From the collection of E.R. Laskowski (1949-2020), a mining engineer who retired to Tucson, Arizona. Laskowski self-collected this specimen July 31, 2001.