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Parauranofana

Parauranofana is a mineral with formula Ca(UO₂)₂(SiO₃OH)₂·5H₂O, in the Silicatos group. This specimen comes from Rössing Uranium Mine, Arandis, Erongo, Erongo Region, Namibia and joined the Terrium collection in 2026.

Parauranofana from Rössing Uranium Mine, Arandis, Erongo, Erongo Region, Namibia — Terrium

Description

Carpet of intense yellow parauranophane rosettes, with bright, well-defined crystals. Intergrowths with quartz crystals. Well-developed rosette aggregates; shows very well under the loupe.

History of this specimen

Its previous owner, Bernhard Dünkel, was a Bavarian tax adviser and founder of Dünkel & Partner; he passed away a few years ago.

About Parauranofana

A scientific rarity. Parauranophane is an uncommon uranyl silicate, dimorphous with uranophane: they share the same chemical composition but have different crystal structures, so they are regarded as separate species. Whereas uranophane typically occurs in acicular or fibrous aggregates, parauranophane develops radiating laminar aggregates forming "rosettes" or "flowers". Specimens with well-developed, voluminous rosettes, like this, are valued for an aesthetic extremely uncommon for the species.

About the locality

Rössing is one of the largest open-pit uranium deposits in the world and a reference locality for secondary uranium minerals. It was discovered in 1928 and belongs to Rio Tinto. The material comes from supergene alteration zones on granitic rock, where well-crystallised associations develop, as in this case. The mine remains active at an industrial scale, but access to collectable material is extremely limited.

Technical data

Catalogue No.
0333
Composition
Ca(UO₂)₂(SiO₃OH)₂·5H₂O
Name
Parauranofana
Group
Silicatos
Category
Núcleus Ardens
Matrix
Granítica
Associations
cuarzo
Mine
Rössing Uranium Mine
District / Municipality
Arandis
Province
Erongo
Region
Erongo Region
Country
Namibia
Size (cm)
7 x 6 x 5
Weight
210.9 g
Acquired
2026
Ex-collection
Bernhard Dünkel
Etymology
From the Greek roots κονία (konis, dust) and χαλκος (chalkos, copper), chosen by Breithaupt and Fritzsche to reflect its physical appearance and metallic content.
Quality
Top
Value trend
Al alza

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