TERRIUM — A mineralogy cabinet


Aerinita fibrosa

Aerinita is a mineral with formula (Ca,Na)₆(Fe³⁺,Fe²⁺,Mg,Al)₄(Al,Mg)₆Si₁₂O₃₆(OH)₁₂(CO₃)·12H₂O, in the Silicatos group. This specimen comes from Embalse Santa Ana (presa de Canelles), Estopiñán del Castillo, Huesca, Aragón, España and joined the Terrium collection in 2004.

Aerinita fibrosa from Embalse Santa Ana (presa de Canelles), Estopiñán del Castillo, Huesca, Aragón, España — Terrium

Description

Fibrous mineral of deep blue colour, with a soft texture and a waxy feel. Displays clearly visible fibres on matrix, in a substantial and well-balanced specimen.

History of this specimen

Acquired from the personal collection of Aleydis Soliveres (Catalog No. 1364), this specimen remains in excellent condition despite its inherent fragility. Soliveres is a renowned field collector of this mineral, with some of his finest discoveries currently featured in several museum displays.

About Aerinita

Silicato complejo hidratado y carbonatado de calcio, sodio, hierro, aluminio y magnesio. Although discovered in 1876, aerinite puzzled scientists for more than a century: its crystal structure was so complex that many thought it was a mixture of minerals. In 2004 a team in Barcelona (Jordi Rius et al.) resolved the structure, a milestone that confirmed its validity to the IMA. It is also a historic pigment, the "Blue of the Pyrenees", used by Romanesque painters for the mantles of the Virgin and the Pantocrator of Taüll as an alternative to the unattainable Afghan lapis lazuli. Its rarity, unusual colouration and restricted origin make it sought after in scientific and collecting circles.

About the locality

TYPE LOCALITY. The Santa Ana Reservoir (Canelles dam), at Estopiñán del Castillo (Huesca), is the type locality of aerinite. It occurs in Triassic Keuper sediments, forming fibres between dolomites and gypsum. Extraction has always been artisanal, hard, and highly dependent on the water level of the reservoir.

Technical data

Catalogue No.
0019
Composition
(Ca,Na)₆(Fe³⁺,Fe²⁺,Mg,Al)₄(Al,Mg)₆Si₁₂O₃₆(OH)₁₂(CO₃)·12H₂O
Name
Aerinita
Variety
fibrosa
Group
Silicatos
Category
Meritum Persé
Matrix
Ofita
Mine
Embalse Santa Ana (presa de Canelles)
District / Municipality
Estopiñán del Castillo
Province
Huesca
Region
Aragón
Country
España
Size (cm)
10 x 8 x 4
Weight
95 g
Acquired
2004
Ex-collection
Aleydis Soliveres
Etymology
From the Greek "aerinos" (ἀέρινος), meaning 'sky-blue' or 'relating to the air or the sky'. Named in 1876 by Arnold von Lasaulx.
Quality
Top
Value trend
Estable

Related specimens

← Back to Terrium catalogue