Linarite - Encyclopedia

    Class : Sulphates, chromates, molybdates
    Subclass : Anhydrous sulfates
    Crystal system : Monoclinic
    Chemistry : PbCuSO4(OH)2
    Rarity : Fairly rare

Linarite is a mineral from the oxidation zone of copper deposits, where its formation is favored by the presence of galena and by slightly acidic conditions. Its name comes from its site of discovery : Linares in Spain. It occurs in elongated prismatic crystals, often tabular or lanceolate, isolated or in groups, in encrustations or in tufted crystalline aggregates, of a deep azure blue color. This color similar to that of azurite is probably the source of much confusion : linarite is perhaps more common than is generally admitted. It is a mineral that has no particular use and remains relatively unknown to collectors.

Linarite in the World

First described in millimetric specimens at Linares (Spain), linarite was then encountered in the mines of Arizona, at Mammoth-St-Anthony and Grand Reef which provided magnificent crystals, respectively 12 and 5 cm in size, the finest known. Excellent crystals also come from Leadhillis (Scotland), and from the Caldbeck Fells mines in Cumberland (England), where they reach 2 cm. Linarite was abundant in the 1920's in Australia's large zinc-lead mine at Broken Hill.

Linarite in France

In France, linarite is known in small fibroradiated groups at Argentolles (Saône-et-Loire), and reported in the mines of Anglais (Cantal) and Alzen (Ariège).

Twinning

This mineral species twins on {100} and more rarely on {001}.

Fakes and treatments

No fake recorded for this mineral species which can easily be confused with azurite.


Hardness : 2.5
Density : 5.35
Fracture : Conchoidal
Trace : Blue

TP : Translucent to transparent
RI : 1.809 to 1.859
Birefringence : 0.050
Optical character : Biaxial -
Pleochroism : Visible
Fluorescence : None

Solubility : Nitric acid

Magnetism : None
Radioactivity : None