Wavellite on Quartz
Siglo Veinte Mine, Llallagua, Rafael Bustillo Province, Potosí, Bolivia
Dimensions: 5.8 × 3.4 × 2.2 cm
Provenance: Original collection label, catalog no. 540, identifying the specimen as wavellite on quartz from Llallagua, Bolivia.
An intricate specimen featuring numerous rounded aggregates of pale buttery-yellow wavellite, densely covered with sparkling microcrystals. The aggregates form a sculptural arrangement across a contrasting matrix of translucent to colorless quartz crystals. Along the reverse, delicate radiating sprays and fan-shaped formations reveal the mineral's distinctive fibrous crystal growth.
Wavellite is a hydrated aluminum phosphate mineral that commonly forms radiating, spherical, and hemispherical aggregates of slender crystals. It typically develops in low-temperature, phosphate-bearing environments, including the alteration zones of mineral deposits.
The Siglo Veinte Mine, part of the historic Llallagua tin-mining district, is renowned for its diverse mineral assemblages and exceptional hydrothermal mineralization. Once among Bolivia's most important tin-producing operations, the mine has also yielded distinctive phosphate minerals, including attractive wavellite specimens associated with quartz.
