Aerenita

Description

Bluish fibres with waxy lustre on matrix.

About Aerenita

Chemically it is a chlorine-hydroxy-borosilicate of calcium and aluminium that represents a major success for Spanish science. Although discovered in 1876, its exceedingly complex crystal structure remained an enigma for more than a century, prompting some to doubt it was even a real mineral. The mystery was resolved in 2004, when a Barcelona team led by Jordi Rius deciphered it and confirmed its validity with the IMA. It is also a historic pigment: the "Blue of the Pyrenees" used by Romanesque masters to paint the Virgin's mantles and the Pantocrator of Sant Climent de Taüll, achieving that characteristic blue without resorting to the costly lapis lazuli imported from Afghanistan.

About the locality

It is the global type locality: the area around the Santa Ana reservoir, at Estopiñán del Castillo (Huesca). Here it formed in Triassic Keuper sediments, growing as fibrous veins between masses of gypsum and dolomite. Its search and extraction have always been artisanal and hard, entirely conditioned by rises and falls in the reservoir's water level.

Technical data

Catalogue No.

0498

Internal reference

X0006

Composition

(Ca,Na)₆(Fe³⁺,Fe²⁺,Mg,Al)₄(Al,Mg)₆Si₁₂O₃₆(OH)₁₂(CO₃)·12H₂O

Name

Aerenita

Group

Silicatos (Inosilicatos)

Mine

Embalse Santa Ana (presa de Canelles)

District / Municipality

Estopiñán del Castillo

Province

Huesca

Region

Aragón

Country

España

Size (cm)

5 x 4 x 2

Acquired

2004

Ex-collection

Aleydis Soliveres

Etymology

From the Greek "aerinos" (ἀέρινος), meaning "airy" or "colour of the sky", in reference to its blue colour.

Quality

Buena

Value trend

Estable

Related specimens

• Abellaíta — España
• Abernathyita — España
• Abernathyita — España
• Abernathyita — España
• Aerinita (fibrosa) — España
• Analcima — España
• Analcima — España
• Analcima — España