Linarite facts for kids

Quick facts for kids Linarite
General
Category	Sulfate minerals
Formula (repeating unit)	PbCu[(OH)2|SO4]
Strunz classification	7.BC.65
Crystal symmetry	P21/m
Unit cell	a = 9.701(2), b = 5.65 c = 4.69 [Å]; β = 102.65°; Z = 2
Identification
Color	Deep azure blue
Crystal habit	Crystals elongated and tabular; in crusts and aggregates
Crystal system	Monoclinic
Twinning	Common on {100}, also on {001}
Cleavage	Perfect on {100}, imperfect on {001}
Fracture	Conchoidal
Mohs scale hardness	2.5
Luster	Sub-adamantine, vitreous
Streak	Pale blue
Diaphaneity	Transparent, translucent
Specific gravity	5.3 - 5.5
Optical properties	Biaxial (-)
Refractive index	nα = 1.809 nβ = 1.838 nγ = 1.859
Birefringence	δ = 0.050
Pleochroism	X = pale blue; Y = blue; Z = Prussian blue
2V angle	Measured: 80°

Linarite is a beautiful and somewhat rare mineral. It is famous among mineral collectors for its amazing, bright blue color.

This mineral forms when other minerals like galena (a lead sulfide) and chalcopyrite (a copper sulfide) break down. This process is called oxidation, which is like rusting. Linarite is made of copper, lead, sulfate, and hydroxide. Its chemical formula is PbCuSO₄(OH)₂.

Linarite crystals often look like long, flat shapes or irregular clumps. It can sometimes be mistaken for another blue mineral called azurite. However, you can tell them apart because linarite does not fizz or react with weak hydrochloric acid, but azurite does. Linarite is also quite soft, with a Mohs hardness of 2.5. This means you could scratch it with a fingernail. It is also quite heavy for its size, with a specific gravity (density) of 5.3 to 5.5.

Discovery and Name

Linarite was first found and identified in 1822. It got its name from the Linares Plateau in Spain, where it was discovered.

Where Linarite is Found

You can often find linarite growing alongside other interesting minerals. These include brochantite, anglesite, caledonite, leadhillite, cerussite, malachite, and hemimorphite.

Image gallery

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  A shallow pocket of crystals of an intense cobalt blue, from Darwin, Darwin District, Inyo County, California, USA

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  Linarite with malachite, Blanchard Mine, Hansonburg District, Socorro County, New Mexico USA (Size: 1.1 x 0.8 x 0.4 cm)

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  Linarite with caledonite, from Baker, El Dorado County, California USA (Size 5.4 x 5.2 x 3.2 cm)

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  Unusual cerussite with a coating ingrained into the surface of microcrystalline malachite and linarite that give it a rich blue-green color

See also

In Spanish: Linarita para niños