Uranoespatita
Uranoespatita is a mineral with formula (Al,□)(UO₂)₂(PO₄)₂F·20(H₂O,F), in the Fosfatos group. This specimen comes from Pedro Álvaro, Villares de Yeltes, Salamanca, Castilla y León, España.
Description
Intense yellow powdery coatings and aggregates spread across much of the ferruginous matrix, with a higher concentration in the upper area. Shows intense green fluorescence under ultraviolet light.
History of this specimen
It retains its original handwritten label, which identifies the specimen as "Uranospathite" and describes "honey-yellow microcrystals" on matrix (best viewed with a loupe), from Pedro Álvaro, Salamanca. Some believe it may have transformed into sabugalite through dehydration, but there are no analyses to confirm this. Carlos Prieto Paramio purchased it from the legendary dealer and collector Joan Montal.
About Uranoespatita
Uranospathite is a quite rare hydrated uranyl aluminium phosphate. Its formula contains an unusual symbol, □, representing a crystallographic vacancy: a position in the crystal structure that may remain empty rather than being occupied by aluminium. It readily loses between 10 and 12 water molecules and can transform into sabugalite. For this reason, some older specimens labelled as uranospathite may now actually be sabugalite, although an analysis would be needed to confirm this in the present specimen.
About the locality
San Valentín, in Pedro Álvaro, is one of Spain's classic localities for secondary uranium phosphates. Alteration of primary uranium minerals produced species such as autunite, uranoespathite, sabugalite and others of the autunite group, valued by collectors for their historical interest.
Technical data
- Catalogue No.
- 0685
- Composition
- (Al,□)(UO₂)₂(PO₄)₂F·20(H₂O,F)
- Name
- Uranoespatita
- Group
- Fosfatos
- Category
- Núcleus Ardens
- Matrix
- Matriz ferruginosa silícea
- Mine
- Pedro Álvaro
- District / Municipality
- Villares de Yeltes
- Province
- Salamanca
- Region
- Castilla y León
- Country
- España
- Size (cm)
- 5.6 x 3.6 x 1.8
- Weight
- 23.8 g
- Ex-collection
- Carlos Prieto Paramio
- Etymology
- From uranium and the Greek «spathē» («sword» or «broad blade»), referring to the shape of its crystals.
- Quality
- Notable
- Value trend
- Al alza
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