Partitioning of Sr between coexisting minerals of the hollandite- and piemontite-groups in a quartz-rich schist from the Sanbagawa metamorphic belt, Japan
-
Masaki Enami
and
Yasuyuki Banno
Abstract
Coexisting minerals of the hollandite-cryptomelane series, piemontite-group, and abswurmbachite-braunite series occur as a small nodule in a quartzose schist (metachert) from the epidote-amphibolite facies area of the Sanbagawa metamorphic belt, central Shikoku, Japan. Strontium, Ba. K. and Pb contents of the hollandite-cryptomelane minerals are 0.00-0.42, 0.07-0.99, 0.00-0.75 and 0.00-0.05 apfu (atoms per formula unit: O = 16), respectively. The piemontite-group minerals can be divided into common piemontite (Ca > Sr in the ten-coordinated A2-site) and strontiopiemontite (Sr > Ca). Strontium. Ba and Pb contents of the strontiopiemontite reach 0.71, 0.26 and 0.20 apfu (O = 12.5), respectively, suggesting the existence of two possible new end- members for epidote-group minerals: “Ba-piemontite [BaCa(Mn3+, Fe3+, Al)3Si3O12(OH)]” and "Pb- piemontite [PbCa(Mn3+, Fe3+, Al)3Si3O12(OH)]”. The abswunnbachite-braunite series minerals (Cu = 0.30-0.53 apfu: O = 12) contain up to 0.34 apfu Mg, indicating the exchange Mg(Mn2+, Cu)-1. Distribution coefficients for Sr between the hollandite-cryptomelane series and the piemontite-group minerals are up to 20. implying that the hollandite-type structure with its large open tunnel is more suitable for incorporation of Sr than the A2-site of the piemontite-group minerals. A synthetic aluminosilicate analogue of the hollandite-cryptomelane compound is stable under P > 8-10 GPa. and suggests the hollandite-type aluminosilicate may be a reservoir of Sr and other large-ion-lithophile elements in the upper mantle.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Partitioning of Sr between coexisting minerals of the hollandite- and piemontite-groups in a quartz-rich schist from the Sanbagawa metamorphic belt, Japan
- Crystallization processes in migmatites
- Amblygonite-montebrasite solid solutions as monitors of fluorine in evolved granitic and pegmatitic melts
- Reduction of water loss from gold-palladium capsules during piston-cylinder experiments by use of pyrophyllite powder
- Trace-element partitioning between immiscible lunar melts: An example from naturally occurring lunar melt inclusions
- Assemblages with titanite (CaTiOSiO4), Ca-Mg-Fe olivine and pyroxenes, Fe-Mg-Ti oxides, and quartz: Part I. Theory
- Assemblages with titanite (CaTiOSiO4), Ca-Mg-Fe olivine and pyroxenes, Fe-Mg-Ti oxides, and quartz: Part II. Application
- The stability of clinopyroxene in the system CaO-MgO-SiO2-TiO2 (CMST)
- Ordering kinetics of Mg-Fe2+ exchange in a Wo43En46Fs11 augite
- Al,Si order in the crystal structure of α-eucryptite (LiAlSiO4)
- TEM-EDX study of weathered layers on the surface of volcanic glass, bytownite, and hypersthene in volcanic ash from Sakurajima volcano, Japan
- Electron microscopic study of the dehydration of diaspore
- Crystal properties and energetics of synthetic kaolinite
- Structures and energies of AlOOH and FeOOH polymorphs from plane wave pseudopotential calculations
- XPS measurement of fivefold and sixfold coordinated sulfur in pyrrhotites and evidence for millerite and pyrrhotite surface species
- Structure of synthetic 6-line ferrihydrite by electron nanodiffraction
- Atomic structures of planar defects in oxybiotite
- Potassium hydrogen disilicate: A possible model compound for 17O NMR spectra of hydrous silicate glasses
- Strain analysis of phase transitions in (Ca,Sr)TiO3 perovskites
- Triclinic liddicoatite and elbaite in growth sectors of tourmaline from Madagascar
- Letter. A simple inorganic process for formation of carbonates, magnetite, and sulfides in martian meteorite ALH84001
Articles in the same Issue
- Partitioning of Sr between coexisting minerals of the hollandite- and piemontite-groups in a quartz-rich schist from the Sanbagawa metamorphic belt, Japan
- Crystallization processes in migmatites
- Amblygonite-montebrasite solid solutions as monitors of fluorine in evolved granitic and pegmatitic melts
- Reduction of water loss from gold-palladium capsules during piston-cylinder experiments by use of pyrophyllite powder
- Trace-element partitioning between immiscible lunar melts: An example from naturally occurring lunar melt inclusions
- Assemblages with titanite (CaTiOSiO4), Ca-Mg-Fe olivine and pyroxenes, Fe-Mg-Ti oxides, and quartz: Part I. Theory
- Assemblages with titanite (CaTiOSiO4), Ca-Mg-Fe olivine and pyroxenes, Fe-Mg-Ti oxides, and quartz: Part II. Application
- The stability of clinopyroxene in the system CaO-MgO-SiO2-TiO2 (CMST)
- Ordering kinetics of Mg-Fe2+ exchange in a Wo43En46Fs11 augite
- Al,Si order in the crystal structure of α-eucryptite (LiAlSiO4)
- TEM-EDX study of weathered layers on the surface of volcanic glass, bytownite, and hypersthene in volcanic ash from Sakurajima volcano, Japan
- Electron microscopic study of the dehydration of diaspore
- Crystal properties and energetics of synthetic kaolinite
- Structures and energies of AlOOH and FeOOH polymorphs from plane wave pseudopotential calculations
- XPS measurement of fivefold and sixfold coordinated sulfur in pyrrhotites and evidence for millerite and pyrrhotite surface species
- Structure of synthetic 6-line ferrihydrite by electron nanodiffraction
- Atomic structures of planar defects in oxybiotite
- Potassium hydrogen disilicate: A possible model compound for 17O NMR spectra of hydrous silicate glasses
- Strain analysis of phase transitions in (Ca,Sr)TiO3 perovskites
- Triclinic liddicoatite and elbaite in growth sectors of tourmaline from Madagascar
- Letter. A simple inorganic process for formation of carbonates, magnetite, and sulfides in martian meteorite ALH84001
