Hausmannite

• Blättricher black-brown stone
• Black Braunsteinerz
• Schwarzmanganerz
• Gloss Braunstein

Hausmannite, outdated also known as Blättricher black-brown stone, black - Braunsteinerz, Schwarzmanganerz and shine Braunstein, is a mineral from the mineral class of " oxides and hydroxides ", which in part may be abundant in different sites though, but overall not very common. It crystallizes in the tetragonal crystal system with the composition Mn2 Mn3 O4 2, ie chemically is a manganese (II, III ) oxide.

Hausmannite developed mainly pseudooctahedral crystals, but also granular to massive aggregates of dark brown, black or gray color with dark red to reddish brown internal reflections.

Etymology and history

The mineral was first described in 1813 by Friedrich Hausmann ( 1782-1859 ), who described it in his "Handbook of Mineralogy " as Blättricher black-brown stone and as a locality honor Stock at Ilmenau in Thuringia stated (now Oehrenstock ).

An earlier report of 1789 found indeed in the mineral system of Abraham Gottlob Werner ( 1749-1817 ), but are in addition to the listing of the name Black - Braunsteinerz made ​​no further information and therefore the name can only be assigned to the hausmannite, because later mineralogists at the description on the Wernersche Black Braunsteinerz relate.

The name is still used today Hausmannite goes back to Wilhelm Ritter von Haidinger, 1828 named the mineral in honor of its describer Hausmann.

Other synonymous terms for the Hausmannite include Schwarzmanganerz in the records Karstens of 1808 and also marked by Hausmann 1847 term gloss brown stone.

Classification

Already in the now outdated but still in use 8th edition of the mineral classification by Strunz was one of hausmannite to mineral class of " oxides and hydroxides " and then to the Department of " oxides with the molar ratio of metal: oxygen = 3: 4 ," where he along with Filipstadit, Hetaerolith, Hydrohetaerolith, Iwakiit, Marokit and Tegengrenit named after him " hausmannite group " with the system no. IV/B.05 formed.

The 9th edition used since 2001, valid and of the International Mineralogical Association (IMA ) of the Strunz'schen Mineral classification assigns the Hausmannite also in the class of " oxides and hydroxides " and there in the department of " oxides with the molar ratio of metal: oxygen = 3: 4 and comparable " one. This division, however, is further divided according to the size of the cations involved, so that the mineral is "With only medium-sized cations " to find according to its composition in the subdivision where it also as a name the " Hausmannite group " with the system no. Forms 4.BB.10 and the other members Hetaerolith, Hydrohetaerolith and Iwakiit.

The mainly common in English-speaking classification of minerals according to Dana assigns the hausmannite in the class of " oxides and hydroxides " and there in the department of " Oxidminerale " one. Here he is as together with Hetaerolith and Hydrohetaerolith in the unnamed group " (B2 A ) 2X4, multiple oxides spinel group " to find 07:02:07 within the subdivision of.

Modifications and varieties

The Arseniodialytit to November 2006 still treated as a separate mineral was identified as a variety of hausmannite.

Education and Locations

Hausmannite usually formed by hydrothermal processes in manganese-containing iron ore junctions, but can also be caused by contact metamorphism. Accompanying minerals occur among others andradite, barite, Braunite, Jacobsite, pyrolusite and rhodochrosite.

Except at its type locality Oehrenstock the mineral has been found in many other regions of Germany, so among other things in Baden- Württemberg ( Black Forest), Bavaria ( Spessart ), Hesse (Limburg ), Lower Saxony ( Peine ), North Rhine -Westphalia (winner country ) Rhineland -Palatinate (Hunsrück ), Saxony -Anhalt (resin) and Saxony (Erzgebirge).

Worldwide, so far (as of 2012) about 280 localities for Hausmannite as known, including New South Wales, Queensland and South Australia in Australia; Iténez province and province of Chiquitos in Bolivia; Minas Gerais in Brazil; several regions in the People's Republic of China; Franche- Comté and Midi-Pyrénées in France; the Cyclades in Greece; England and Wales in the United Kingdom; Orissa in India; several regions in Italy; Honshu, Kyushu and Shikoku in Japan; Souss- Massa- Daraâ in Morocco; Durango in Mexico; Otjozondjupa in Namibia; Nord-Trøndelag and Telemark in Norway; al - Batinah in Oman; Carinthia and Salzburg in Austria; the Ural Mountains in Russia; several regions in Sweden; the cantons of Graubünden, St. Gallen and Valais in Switzerland; Banská Bystrica and Nitra in Slovakia; the Northern Cape and North West provinces in South Africa; Denizli in Turkey; many regions in the United States; Khor Fakkan and Fujairah in the United Arab and Emirates.

Morphology

The crystals of Hausmannits are similar to the spinel from pyramidal to octahedral character, however, provided with horizontal stripes. The striations reveals the twin nature of the crystals, which often consist of five cyclic fused together individuals.

Crystal structure

Hausmannite crystallizes in the tetragonal crystal system in space group I41/amd ( Raumgruppen-Nr. 141) with the lattice parameters a1 = a2 = 5.76 Å and c = 9.44 Å and four formula units per unit cell.

Use

Hausmannite is an important ore for the extraction of manganese.