+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Armbrusterite, K sub 5 Na sub 6 Mn super 3+ Mn sub 14 super 2+ sub 4 OH sub 10 4H sub 2 O; a new Mn hydrous heterophyllosilicate from the Khibiny alkaline massif, Kola Peninsula, Russia



Armbrusterite, K sub 5 Na sub 6 Mn super 3+ Mn sub 14 super 2+ sub 4 OH sub 10 4H sub 2 O; a new Mn hydrous heterophyllosilicate from the Khibiny alkaline massif, Kola Peninsula, Russia



American Mineralogist 92(2-3): 416-423



Armbrusterite, ideally K (sub 5) Na (sub 6) Mn (super 3+) Mn (sub 14) (super 2+) [Si (sub 9) O (sub 22) ] (sub 4) (OH) (sub 10) .4H (sub 2) O, is a new silicate of potassium, sodium, and manganese found in a thin cancrinite-aegirine-microcline vein within urtite at Mt. Kukisvumchorr. The mineral occurs in intimate association with raite. Other associated minerals are lamprophyllite, mangan-neptunite, pectolite, vinogradovite, calcite, molybdenite, galena, sphalerite, and fluorite. Armbrusterite occurs as split, curved crystals and spherulites (< or =2 mm diameter). The mineral is translucent (transparent in thin fragments), dark reddish-brown. It has vitreous luster and light-brown streak. Cleavage is perfect on (001) and the fracture is uneven. Mohs hardness is about 3.5. In transmitted light, the mineral is reddish-brown, with strong pleochroism: X = light yellowish-brown, Y and Z = dark reddish-brown; dispersion r>v, weak. Armbrusterite is biaxial (-): alpha = 1.532(2), beta = 1.560(2), gamma = 1.564(2) (for lambda = 589 nm), 2V varies from 10 degrees to 20 degrees . Optical orientation: X is perpendicular to (001). The mean chemical composition determined by electron microprobe and the Penfield method (for H (sub 2) O) is (wt%): Na (sub 2) O 5.26, MgO 0.19, Al (sub 2) O (sub 3) 0.04, SiO (sub 2) 56.02, K (sub 2) O 6.13, CaO 0.26, TiO (sub 2) 0.04, MnO 23.62, Mn (sub 2) O (sub 3) 2.07, FeO 0.65, ZnO 0.20, H (sub 2) O 4.1, sum. 98.58. Empirical formula calculated on the basis of Si = 36 is K (sub 5.03) Na (sub 6.55) (Mn (sub 12.86) (super 2+) Mn (sub 1.01) (super 3+) Fe (sub 0.35) (super 2+) Mg (sub 0.18) Ca (sub 0.18) Zn (sub 0.09) Al (sub 0.03) Ti (sub 0.02) ) (sub Sigma = 14.72) [Si (sub 36) O (sub 88) ](OH) (sub 10.10) .3.75 H (sub 2) O. Armbrusterite is monoclinic, C2/m, a = 17.333(2), b = 23.539(3), c = 13.4895(17) Aa, beta = 115.069(9) degrees , V = 4985.4(11) Aa (super 3) , Z = 2. The strongest X-ray powder-diffraction lines are [d in Aa, (I), (hkl)]: 12.28 (100) (001), 4.10 (10) (003), 3.562 (10) (113, 261), 3.260 (18) (114), 3.117 (13) (203), 3.077 (54) (004), 2.622 (10) (371). The crystal structure of armbrusterite was refined to R (sub 1) = 0.085 on the basis of 3960 unique observed reflections. The structure is based upon double silicate [Si (sub 9) O (sub 22) ] layers consisting of 5-, 6-, 7-, and 8-membered tetrahedra rings. The layers are linked via octahedral sheets formed by Na and Mn octahedra. The interior of the double silicate layers is occupied by K (super +) cations and H (sub 2) O molecules. The mineral is named in honor of Thomas Armbruster (b. 1950; University of Berne) for his outstanding contribution to structural mineralogy and crystallography, especially to the study of Mn-rich minerals.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 030172739

Download citation: RISBibTeXText


Related references

Armbrusterite, K5Na6Mn3+Mn142+[Si9O22]4(Oh)10{middle dot}4H2O, a new Mn hydrous heterophyllosilicate from the Khibiny alkaline massif, Kola Peninsula, Russia. American Mineralogist 92(2-3): 416-423, 2007

Pyroxenes from the Khibiny alkaline massif Kola Peninsula, Russia. Proceedings of the Russian Mineralogical Society 137.2, 2008

Chromium mineralization in the Khibiny alkaline massif (Kola Peninsula, Russia). Moscow University Geology Bulletin 64(4): 220-229, 2009

Fivegite K4 Ca2 AlSi7 O17 O2-x OHx H2 O2-x OHx Cl; a new mineral from the Khibiny alkaline massif Kola Peninsula, Russia. Proceedings of the Russian Mineralogical Society 139.4: 47-63, 2010

Kihlmanite-(Ce), Ce 2 TiO 2 [SiO 4 ](Hco 3 ) 2 (H 2 O), a new rare-earth mineral from the pegmatites of the Khibiny alkaline massif, Kola Peninsula, Russia. Mineralogical Magazine 78(3): 483-496, 2014

Andrianovite, Na12 K,Sr,Ce3 Ca6 Mn3 Zr3 NbSi25 O73 O,H2 O,OH5; new potassic mineral of eudialyte group from Khibiny alkaline; massif, Kola Peninsula, Russia. Proceedings of the Russian Mineralogical Society 137.2, 2008

Kazanskyite, Ba & TiNbNa 3 Ti(Si 2 O 7 ) 2 O 2 (Oh) 2 (H 2 O) 4 , a Group-Iii Ti-disilicate mineral from the Khibiny alkaline massif, Kola Peninsula, Russia: description and crystal structure. Mineralogical Magazine 76(3): 473-492, 2012

Nafertisite, Na 3 Fe 2+ 10 Ti 2 (Si 6 O 17 ) 2 O 2 (Oh) 6 F(H 2 O) 2 , from Mt. Kukisvumchorr, Khibiny alkaline massif, Kola peninsula, Russia: Refinement of the crystal structure and revision of the chemical formula. European Journal of Mineralogy 26(5): 689-700, 2014

Kazanskyite, BaTiNbNa3 TiSi2 O7 2 O2 OH2 H2 O4; a Group-III Ti-disilicate mineral from the Khibiny alkaline massif, Kola Peninsula,; Russia; description and crystal structure. Mineralogical Magazine 76.3, 2012

Davinciite, Na12 K3 Ca6 Fe32+ Zr3 Si26 O73 OHCl2; a new K, Na-ordered mineral of the eudialyte group from the Khibiny alkaline; massif, Kola Peninsula, Russia. Proceedings of the Russian Mineralogical Society 141.2, 2012

Caryochroite a new heterophyllosilicate mineral species related to nafertisite from the Lovozero Massif, Kola Peninsula, Russia. The Canadian Mineralogist 44, Part 6: 1331-1340, 2006

Shlykovite KCaSi4 O9 OH 3H2 O and cryptophyllite KCaSi4 O10 5H2 O; new minerals from the Khibiny alkaline massif, Kola Peninsula, Russia. Proceedings of the Russian Mineralogical Society 139.1: 37-50, 2010

Excess argon-40 in nepheline from the Kovdor Massif (Kola Peninsula) according to (super 39) Ar- (super 40) Ar data. Geokhimiya 1987(6): 840-846, 1987

Comparison of Rb-Sr and (super 40) Ar- (super 39) Ar geochronology of hornblende from the Precambrian of the Kola Peninsula, Russia, using microsampling techniques. Program with Abstracts - Geological Association of Canada(Mineralogical Association of Canada(Canadian Geophysical Union, Joint Annual Meeting 23: A34, 1998

Gladiusite, Fe (super 3+) (sub 2) (Fe (super 2+) ,Mg) (sub 4) (PO (sub 4) )(OH) (sub 11) (H (sub 2) O), a new hydrothermal mineral species from the phoscorite-carbonatite unit, Kovdor Complex, Kola Peninsula, Russia. The Canadian Mineralogist 38, Part 6: 1477-1486, 2000