Hedenbergite

Hedenbergite is a commonly occurring mineral from the mineral class of " silicates and Germanates ". It crystallizes in the monoclinic crystal system with the chemical composition CaFe2 [ Si2O6 ] and developed usually short prismatic, columnar to acicular crystals to about 5 cm size, but also grained, foliated or massive mineral aggregates of dark green, brown green, brown or black in color with white to gray stroke color.

Hedenbergite makes a perfect mixed batch with diopside and Johannsenite.

Etymology and history

Was first found in 1819 on Hedenbergite Tunaberg in Nyköping in Sweden and described by Jöns Jakob Berzelius, of the minerals by MA Ludwig Hedenberg, a Swedish chemist Berzelius and employees ' named.

Classification

In the now outdated but still in use 8th edition of the mineral classification by Strunz the Hedenbergite belonged to the department of " chains and chain silicates ( inosilicates ) ", where he, together with aegirine, augite, diopside, Esseneit, jadeite, Jervisit, Johannsenite, Kanoit, Klinoenstatit, Klinoferrosilit, Kosmochlor, Namansilit, Natalyit, omphacite, Petedunnit, pigeonite and spodumene the " pyroxene, clinopyroxene subgroup " with the system no. VIII/F.01 formed within the pyroxene group.

The 9th edition valid since 2001 and of the International Mineralogical Association (IMA ) used the Strunz'schen Mineral classification assigns the Hedenbergite also included in the department's " chain and chain silicates ( inosilicates ) ". This division, however, is further subdivided according to the type of chain formation, so that the mineral according to its construction in the subsection " chain and chain silicates with 2- periodic single chains Si2O6; Pyroxene family " is to find where it together with augite, Esseneit, hedenbergite, Johannsenite and Petedunnit the ". Ca clinopyroxene, Diopsidgruppe "with the System No. 9.DA.15 forms.

The mainly common in English-speaking classification of minerals according to Dana assigns the hedenbergite in the class of " silicates and Germanates " and there in the department of " chain silicate minerals " one. Here he is with diopside, augite, Johannsenite, Petedunnit, Esseneit and Davisit in the group of " C2 / c clinopyroxene (Ca - clinopyroxene ) " with the system no. 65.01.03a within the subdivision " chain silicates: Simple unbranched chains, W = 1 with chains P = 2" to find.

Education and Locations

Hedenberg forms in metamorphic, calcium-rich rocks such as iron-bearing skarns and pyroxene gneisses. He can also form in alkaline magmatic granites and syenites or in xenoliths of Kimberlith. Accessory mineral in iron formations including the grunerite in granites and syenites, it is mainly Arfvedsonite, fayalite and quartz.

Worldwide, hedenbergite so far (as of 2010) are detected at around 450 localities, so include Afghanistan, Algeria, Antarctic, Argentina, Ethiopia, Australia, Brazil, Bulgaria, Chile, China, Eritrea, Germany, France, Greece, Greenland, Guatemala, Honduras, Indonesia, Israel, Italy, Japan, Cameroon, Canada, Kenya, Colombia, North and South Korea, Kosovo, Madagascar, Morocco, Mexico, Mongolia, Namibia, Nepal, New Zealand, Nigeria, Norway, Oman, Austria, Pakistan, Peru, Poland, Portugal, Romania, Russia, Sweden, Switzerland, Spain, St. Lucia, Slovakia, South Africa, Tajikistan, Turkey, Ukraine, Uzbekistan, the United Kingdom ( UK), in the United States (U.S.), Vietnam and the Western Sahara.

Crystal structure

Hedenbergite crystallizes in the monoclinic space group C2 / c with lattice parameters a = 9.845 Å; b = 9.024 Å; c = 5.245 Å and 104.74 ° β =, and four formula units per unit cell.