TERRIUM — A mineralogy cabinet


Autunita

Autunita is a mineral with formula Ca(UO₂)₂(PO₄)₂·10-12H₂O, in the Fosfatos group. This specimen comes from Nanjingqiao Submarine Mine, Pingjiang, Hunan, China and joined the Terrium collection in 2025.

Autunita from Nanjingqiao Submarine Mine, Pingjiang, Hunan, China — Terrium

Description

Dense carpet of egg-yolk yellow lamellar crystals with green-orange zoning on a layer of prismatic quartz. The crust, c. 6 mm thick, shows strong vitreous lustre and continuous growth. The stratigraphic sequence is clear: granitic base, an intermediate layer of well-crystallised quartz, and an upper autunite coating. A purely aesthetic piece with a perfect stratigraphic layout.

History of this specimen

I bought it from Anja & Phillip Hoeffer, dealers specialised in high-quality radioactive minerals. Nanjingqiao has only started to reach the market in recent years, and they are among the few who have accessed original material (uncut, not rehydrated).

About Autunita

Autunite is a hydrated uranium-calcium phosphate that forms in the oxidised zones of uraniferous deposits. It commonly occurs as tabular or lamellar aggregates with intense green fluorescence under ultraviolet light.

About the locality

The Nanjingqiao Submarine Mine was worked in the 1970s–80s by the Chinese Nuclear Institute as an experimental deposit below the water table. It is now closed and under state control; current specimens come from old stocks released or exchanged among Chinese geologists and technicians, not from recent extractions. Hence their added value.

Technical data

Catalogue No.
0222
Composition
Ca(UO₂)₂(PO₄)₂·10-12H₂O
Name
Autunita
Group
Fosfatos
Category
Núcleus Ardens
Matrix
Cuarzo y granito
Mine
Nanjingqiao Submarine Mine
District / Municipality
Pingjiang
Province
Hunan
Country
China
Size (cm)
5.5 x 3.5 x 2.5
Weight
73 g
Acquired
2025
Etymology
From "Autun", the name of the French locality of Autun, near which it was first described.
Quality
Notable
Value trend
Al alza

Related specimens

← Back to Terrium catalogue