Beudandite is a secondary mineral occurring in the oxidized zones of polymetallic

Polymetal

Primarily used in chemistry or mining, polymetal or polymetallic refers to a substance composed of a combination of different metals. When the substance contains only two metals the term bimetal is sometimes preferred .* A polymetallic ore is...

 deposits. It is a lead

Lead

Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

, iron

Iron

Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

, arsenate

Arsenate mineral

Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the 3- anion group and, more rarely, other arsenates with anions like AsO32- or [AsO22]- . Arsenite minerals are much less common...

, sulfate

Sulfate mineral

The sulfate minerals are a class of minerals which include the sulfate ion within their structure. The sulfate minerals occur commonly in primary evaporite depositional environments, as gangue minerals in hydrothermal veins and as secondary minerals in the oxidizing zone of sulfide mineral deposits...

 with endmember formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

: PbFe₃(OH)₆SO₄AsO₄.

Beudantite is in a subgroup of the alunite

Alunite

Alunite is a sulfate mineral that was first observed in the 15th century in Monti della Tolfa, north of Rome, where it was mined for the manufacture of alum. First called aluminilite by J.C. Delamétherie in 1797, this name was contracted by François Beudant in 1824 to alunite.Distinct crystals of...

 group. It is the arsenate analogue of the phosphate corkite

Corkite

Corkite is a phosphate mineral in the beudantite subgroup of the alunite group. Corkite is the phosphate analogue of beudantite and with it, a complete solid solution range exists. Corkite will also form a solid solution with kintoreite....

. Beudantite also forms a solid-solution

Solid solution

A solid solution is a solid-state solution of one or more solutes in a solvent. Such a mixture is considered a solution rather than a compound when the crystal structure of the solvent remains unchanged by addition of the solutes, and when the mixture remains in a single homogeneous phase...

 with segnitite and plumbojarosite.

It crystallizes in the trigonal 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...

 and shows a variety of crystal habit

Crystal habit

Crystal habit is an overall description of the visible external shape of a mineral. This description can apply to an individual crystal or an assembly of crystals or aggregates....

s including tabular, acute rhombohedral, pseudo-cubic and pseudo-cuboctahedral.

It occurs in association with carminite, scorodite

Scorodite

Scorodite is a common hydrated iron arsenate mineral, with the chemical formula FeAsO4·2H2O. It is found in hydrothermal deposits and as a secondary mineral in gossans worldwide. Scorodite weathers to limonite....

, mimetite

Mimetite

Mimetite, whose name derives from the Greek Μιμητής mimethes, meaning "imitator", is an arsenate mineral which forms as a secondary mineral in lead deposits, usually by the oxidation of galena and arsenopyrite. The name is a reference to mimetite's resemblance to the mineral pyromorphite...

, dussertite, arseniosiderite

Arseniosiderite

Arseniosiderite is a rare arsenate mineral formed by the oxidation of other arsenic-containing minerals, such as scorodite or arsenopyrite. It occurs in association with beudantite, carminite, dussertite, pharmacolite, pitticite, adamite and erythrite. The name arseniosiderite reflects two major...

, pharmacosiderite

Pharmacosiderite

Pharmacosiderite is a hydrated basic ferric arsenate, with chemical formula KFe434·H2O and a molecular weight of 873.38 g/mol. It consists of the elements arsenic, iron, hydrogen, potassium, sodium and oxygen. It has a Mohs hardness of 2 to 3, about that of a finger nail...

, olivenite

Olivenite

Olivenite is a copper arsenate mineral, formula Cu2AsO4OH. It crystallizes in the monoclinic system , and is sometimes found in small brilliant crystals of simple prismatic habit terminated by domal faces...

, bayldonite

Bayldonite

Bayldonite is a rare secondary mineral with the chemical formula PbCu322H2O. It was first discovered in Penberthy Croft Mine, Cornwall, England, UK. It is named after its discoverer, John Bayldon....

, duftite

Duftite

Duftite is a relatively common arsenate mineral with the formula CuPb, related to conichalcite. It is green and often forms botryoidal aggregates. It is a member of the Adelite-Descloizite Group, Conichalcite-Duftite Series. Duftite and conichalcite specimens from Tsumeb are commonly zoned in...

, anglesite

Anglesite

Anglesite is a lead sulfate mineral with the chemical formula PbSO4. It occurs as an oxidation product of primary lead sulfide ore, galena. Anglesite occurs as prismatic orthorhombic crystals and earthy masses, and is isomorphous with barite and celestine. It contains 74% of lead by mass and...

, cerussite

Cerussite

Cerussite is a mineral consisting of lead carbonate , and an important ore of lead. The name is from the Latin cerussa, white lead. Cerussa nativa was mentioned by Conrad Gessner in 1565, and in 1832 F. S. Beudant applied the name cruse to the mineral, whilst the present form, cerussite, is due to...

 and azurite

Azurite

Azurite is a soft, deep blue copper mineral produced by weathering of copper ore deposits. It is also known as Chessylite after the type locality at Chessy-les-Mines near Lyon, France...

.

Discovery

Beudantite was first described in 1826 for an occurrence in the Louise Mine, Wied Iron Spar District, Westerwald

Westerwald

The Westerwald is a low mountain range on the right bank of the River Rhine in the German federal states of Rhineland-Palatinate, Hesse and North Rhine-Westphalia. It is a part of the Rhine Massif...

, Rhineland-Palatinate

Rhineland-Palatinate

Rhineland-Palatinate is one of the 16 states of the Federal Republic of Germany. It has an area of and about four million inhabitants. The capital is Mainz. English speakers also commonly refer to the state by its German name, Rheinland-Pfalz ....

, Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

. It was named after French mineralogist François Sulpice Beudant

François Sulpice Beudant

François Sulpice Beudant , French mineralogist and geologist, was born in Paris.He was educated at the Ecole Polytechnique and Ecole Normale, and in 1811 was appointed professor of mathematics at the lycée of Avignon. Thence he was called, in 1813, to the lycée of Marseilles to fill the post of...

(1787-1850).