Jordanite is a sulfosalt mineral with chemical formula Pb₁₄(As,Sb)₆S₂₃ in the monoclinic crystal system

Crystal system

In crystallography, the terms crystal system, crystal family, and lattice system each refer to one of several classes of space groups, lattices, point groups, or crystals...

, named after the German scientist Dr H. Jordan (1808–1887) who discovered it in 1864.

Lead-grey in colour (frequently displaying an iridescent tarnish), its streak

Streak (mineralogy)

The streak of a mineral is the color of the powder produced when it is dragged across an unweathered surface. Unlike the apparent color of a mineral, which for most minerals can vary considerably, the trail of finely ground powder generally has a more consistent characteristic color, and is thus...

 is black and its lustre

Lustre (mineralogy)

Lustre is a description of the way light interacts with the surface of a crystal, rock, or mineral. The word lustre traces its origins back to the Latin word lux, meaning "light", and generally implies radiance, gloss, or brilliance....

 is metallic. Jordanite has a hardness of 3 on Mohs scale, has a density of approximately 6.4, and a conchoidal fracture

Fracture

A fracture is the separation of an object or material into two, or more, pieces under the action of stress.The word fracture is often applied to bones of living creatures , or to crystals or crystalline materials, such as gemstones or metal...

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The type locality

Type locality (geology)

Type locality , also called type area or type locale, is the where a particular rock type, stratigraphic unit, fossil or mineral species is first identified....

 is the Lengenbach Quarry

Lengenbach Quarry

The Lengenbach Quarry is located in the Binn Valley and it is noted among the mineralogical community for its unusual sulfosalt specimens.-Location:...

 in the Binn

Binn

Binn is a municipality in the district of Goms in the canton of Valais in Switzerland.The Binn valley is known for its rich mineral deposits, some types of which are unique to the area. The notable Lengenbach Quarry is in Binn....

 Valley, Wallis

Valais

The Valais is one of the 26 cantons of Switzerland in the southwestern part of the country, around the valley of the Rhône from its headwaters to Lake Geneva, separating the Pennine Alps from the Bernese Alps. The canton is one of the drier parts of Switzerland in its central Rhône valley...

, Switzerland

Switzerland

Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

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