What is Vandendriesscheite?
Vandendriesscheite is a hydrated lead uranyl oxide, typically yellow and found as a secondary mineral in oxidised uranium deposits.
Mineralogy and structure
Reference formula: Pb1.5(UO2)10O6(OH)11·11H2O. Vandendriesscheite is orthorhombic and belongs to the hydrated uranyl-oxide family. The exact COD 9001891 model is used; hydration and alteration can vary in natural material. Vandendriesscheite is classified with oxides and has orthorhombic crystal symmetry. Typical hardness is 2–3 on the Mohs scale and specific gravity is approximately 5.5–5.8.
Colour, lustre and habit
Typical colours include yellow, orange-yellow, brownish-yellow. The usual platy, crusty, radiating habit and pearly, vitreous, dull lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Vandendriesscheite forms in or is associated with oxidised uranium-lead veins, mine fractures and alteration zones. Important documented localities include the Democratic Republic of the Congo, France, Germany, the Czech Republic and the United States.
Yellow plates from a uranium oxidation zone
Vandendriesscheite is collected for its bright colour and place in uranium mineralogy, but a responsible specimen label must include radioactivity, lead content and secure storage guidance.
Collecting and care
Radioactive and lead-bearing: keep sealed, dry and shielded as appropriate; avoid dust, heat and casual handling.
