Kanoit is a very rarely occurring mineral from the mineral class of " silicates and Germanates ". It crystallizes in the monoclinic crystal system with the chemical composition (Mn 2 1 x, Mg x ) MgSi2O6, with 0.5 > x ≥ 0
The usually only a few millimeters in size crystals are prismatic or irregular grainy. Kanoit is pinkish brown transparent to translucent and has vitreous luster. The density is 3.66 g/cm3, the Mohs hardness is 6
Etymology and history
Was discovered Kanoite in manganese-rich layers hornblendefazieller sediments and basic volcanic rocks on the Oshima Peninsula, Hokkaido, Japan. There Kanoit place along with manganese-rich cummingtonite, Spessartine and relics of Pyroxmangit that have been replaced by Kanoit in the course of metamorphosis.
Was described in 1977 by Hideo Kobayashi Kanoit. He named the new minerals by the Professor of Petrology of the Akita University, Dr. Hiroshi Kano, in recognition of his work on the metamorphic rocks of Japan.
In the now outdated but still in use 8th edition of the mineral classification by Strunz the Kanoit belonged to the department of " chains and chain silicates ( inosilicates ) ", where he, together with aegirine, augite, diopside, Esseneit, jadeite, Jervisit, Johannsenite, hedenbergite, Klinoenstatit, Klinoferrosilit, Kosmochlor, Namansilit, Natalyit, omphacite, Petedunnit, pigeonite and spodumene the subgroup of " clinopyroxene " 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 Kanoit also included in the department's " chain and chain silicates ( inosilicates ) ". However, this is further subdivided according to the crystal structure, 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 Klinoenstatit, Klinoferrosilit, Halagurit pigeonite and the group of". Mg, Fe, Mn clinopyroxene, Klinoenstatitgruppe "with the System No. 9.DA.10 forms.
The mainly common in English-speaking classification of minerals according to Dana assigns the Kanoit in the department of " chain silicate minerals " one. Here he is with Klinoenstatit, Klinoferrosilit and pigeonite in the group of "P2 / c clinopyroxene " with the system no. 65.01.01 within the subdivision " chain silicates: Simple unbranched chains, W = 1 with chains P = 2" to find.
Modifications and varieties
The connection MnMgSi2O6 is polymorphic and Kanoit is the monoclinic low temperature modification. Another modification known is the othorhombische orthopyroxene Donpeacorite.
Education and Locations
Kanoit is likely to form in the manga metamorphosis rich calcareous sediments under conditions of Granulith facies. In such rocks Kanoit occurs together with manganese-rich cummingtonite, Spessartine and Pyroxmangit.
The type locality is the coast near Tatehira on the Oshima Peninsula, Hokkaido, Japan. Other sites are the Shimozuru mine in Kyushu, Japan, the Semail ophiolite in Bulaydah in the Khawr Fakkan massif, Oman, the Balmat -Edwards zinc region in Balmat in New York, USA, and the lead-zinc deposits of Broken Hill in New South Wales, Australia.
In addition, one finds Kanoit in some meteorites.
Kanoit crystallizes in the monoclinic space group P21 / c with the structure of clinopyroxene.
The distribution of manganese on the two octahedral positions is ordered. Almost all of the Mn is found on the more distorted M2 position.