New minerals 2009 approved by IMA CNMNC in October 2009

PROPOSALS APPROVED IN OCTOBER 2009

IMA No. 2009-050
Bonnet Island, Georgian Bay, Parry Sound, Ontario, Canada (UTM coordinates 0567531W 5003719N NAD 83)
Edward S. Grew
{(Y, REE)(Ca, Fe2+)2}[(Mg,Fe2+)(Fe3+,Al)]Si3O12; end member is (Y2Ca)(Mg2)Si3O12
Garnet group
Cubic: Ia-3d; structure determined
a 11.9947(6) Å

IMA No. 2009-051
Upper Chegem volcanic structure, Kabardino-Balkaria, North Caucasus, Russia (43°17'N 43°6.42'E)
Irina O. Galuskina
Ca3U6+ZrFe3+2Fe2+O12
Garnet group
Cubic: Ia-3d; structure determined
a 12.7456(9) Å

IMA No. 2009-052
Upper Chegem volcanic structure, Kabardino-Balkaria, North Caucasus, Russia (43°17'N 43°6'E)
Irina O. Galuskina
Ca3SbSnAl3O12
Garnet group
Cubic: Ia-3d; structure determined
a 12.492(1) Å

IMA No. 2009-053
Upper Chegem volcanic structure, Kabardino-Balkaria, North Caucasus, Russia (43°17'N 43°6.42'E)
Irina O. Galuskina
Ca3SbZrFe3O12
Garnet group
Cubic: Ia-3d; structure determined
a 12.49 Å

IMA No. 2009-054
Wiluy River, Yakutia, Russia (63.0oN 112.3o
Irina O. Galuskina E)
Ca3Sc2Si3O12
Garnet group
Cubic: Ia-3d; structure determined
a 12.255(1) Å

IMA No. 2009-055
Dúbrava Sb deposit, Low Tatra Mountains, Slovak Republic
Dan Topa
Pb15-2xSb14+2xS36Ox (x ~ 0.2)
New structure type
Monoclinic: C2/m; structure determined
a 48.189(48), b 4.1104(40), c 34.235(35) Å, β 106.059(15)°

IMA No. 2009-056
Nishny Tagil ultramafic complex, Solovyeva Gora, Alexandrov Log, Russia (57°40'N 59°39'W) and the Konder placer, Konder alkaline-ultrabasic massif, Maya River basin, South Yakutia, East Siberia, Russia (57°36'N 134°37'W)
Victor D. Begizov
(Fe,Rh,Ni,Ir,Cu,Pt)9S8
Possibly a distorted pentlandite derivative
Tetragonal: Primitive
a 10.009(5), c 9.840(8) Å

IMA No. 2009-057
Kobokobo pegmatite, Kobokobo, South Kivu Province, Democratic Republic of Congo (3º5'S 27º8'E)
Stuart J. Mills
Al6(PO4)4(OH)6∙11H2O
New structure type
Triclinic: P1 or P-1
a 7.399(13), b 7.771(17), c 12.144(16) Å, α 99.03(17), β 91.98(17), γ 116.11(15)º

IMA No. 2009-058
Lengenbach, Binn Valley, Switzerland
Fabrizio Nestola
Tl5-xPb2x(As,Sb)21-xS34
As-dominant analogue of chabournéite (x ~ 1)
Triclinic: P1 (by analogy with chabournéite)
a 16.217(7), b 42.544(9), c 8.557(4) Å, α 95.72(4), β 90.25(4), γ 96.78(4)º

IMA No. 2009-059
Liley, Üdersdorf, Daun, Eifel Mountains, Rheinland-Pfalz, Germany (holotype); Tausonitovaya Gorka, Murun alkaline complex, Irkutsk province, Russia (cotype)
Yulia Uvarova
NaKBaTi2(Si4O12)O2
K analogue of batisite
Orthorhombic: Imma; structure determined
a 8.0884(4), b 10.4970(5), c 13.9372(6) Å

IMA No. 2009-060
Prága Hill, Bazsi, Veszprém County, Transdanubia, Hungary (46°56'N 17°15'E)
Giovanna Vezzalini
(Mg0.7K0.5Ca0.5Na0.1)[Al3Si9O24]·10H2O
Mg-dominant chabazite
Rhombohedral: R-3; structure determined
a 9.3433(5) Å, α 94.894(4)º

IMA No. 2009-062
Tolbachik volcano, Kamchatka, Far-Eastern Region, Russia
Mikhail E. Zelenskiy
Cu3(VO4)2
Dimorph of triclinic mcbirneyite
Monoclinic: P21/c
a 6.2695(4), b 8.0195(3), c 6.3620(3) Å, β 111.96(1) º /с; structure determined

IMA No. 2009-063
Aga mine (35°16.4'N, 116°5.7'W) and the Bird Nest drift (35°16.6'N, 116°6.0'W), Otto Mountain, San Bernardino County, California, USA
Anthony R. Kampf
Pb2TeO5
New structure type
Monoclinic: Cc; structure determined
a 13.099(3), b 5.714(1), c 7.520(2) Å, β 123.80(3)º

IMA No. 2009-064
Aga mine (35°16.4'N, 116°5.7'W) and the Bird Nest drift (35°16.6'N, 116°6.0'W), Otto Mountain, San Bernardino County, California, USA
Anthony R. Kampf
Pb2Cu5(TeO6)2(OH)2
New structure type
Orthorhombic: P21nm
a 5.2000(2), b 9.6225(4), c 11.5340(5) Å nm; structure determined

IMA No. 2009-065
Aga mine (35°16.4'N, 116°5.7'W), Otto Mountain, San Bernardino County, California, USA
Anthony R. Kampf
Pb2Cu4(TeO6)2(H2O)2
New structure type
Orthorhombic: P212121
a 5.2006(5), b 9.6335(10), c 11.6837(13) Å ; structure determined


NOMENCLATURE PROPOSALS APPROVED IN OCTOBER 2009

09-A-bis STANDARDISATION OF MINERAL GROUP HIERARCHIES
Criteria for the definition of mineral groups, and a hierarchical scheme for the nomenclature of groups, have been set up. The latter has been applied to selected cases of existing groups, and will serve as a basis for a forthcoming compilation of mineral groups including as many minerals as possible.

NOMENCLATURE OF THE TOURMALINE GROUP MINERALS
Re-examination and redefinition of tourmaline end-members and potential new end-members and species has undertaken, including a classification guide for naming tourmalines.

PERTSEVITE IS RENAMED PERTSEVITE-(F)
A new mineral from the Snezhnoye deposit, Chersky Mountains, Republic of Sakha-Yakutia, Russian Federation (IMA 2008-060) has been approved by the CNMNC. Its formula is Mg2(BO3)(OH) and it is the OH-dominant analogue of pertsevite, Mg2(BO3)F. In voting comments on the name of the proposed new mineral (IMA 2008-060), six CNMNC members explicitly agreed in having pertsevite renamed as pertsevite-(F); only one member asked for an official decision by CNMNC. Accordingly, the Chair of CNMNC has authorised the renaming of pertsevite as pertsevite-(F) in order to standardise the nomenclature in the pertsevite group.

IMA 09-B DISCREDITATION OF PARASPURRITE, THE MONOCLINIC POLYMORPH OF SPURRITE
Paraspurrite is discredited. It corresponds to polysynthetically twinned spurrite.

IMA 09-C MOSANDRITE: REDEFINITION OF ITS COMPOSITION. RINKITE IS NO MORE QUESTIONABLE
Mosandrite is a mineral species belonging to the rinkite group and differing from rinkite in its chemical, crystallographic and structural features. The formula of mosandrite is redefined as Ti(□,Ca,Na)3(Ca,REE)4(Si2O7)2[H2O,OH,F]4·H2O. Rinkite is no more a questionable (Q) species, but a fully valid member, together with mosandrite and nacareniobsite-(Ce), of the rinkite group of minerals.



Edited 2 time(s). Last edit at 11/09/2009 10:25AM by Marco E. Ciriotti.

IMA 2009-059 was previously described, but non approved, with the name of "noonkanbahite".

References:
• Prider, R.T. (1965): Noonkanbahite, a potassic batisite from the lamproites of Western Australia. Mineralogical Magazine, 34, 403-405.
• Rastsvetaeva, R.K., Pushcharovsky, D.Yu., Konev, A.A., Evsyunin, V.G. (1997): Kristallografiya, 42, 837-840.
• Uvarova, Y.A., Sokolova, E., Hawthorne, F.C., Liferovich, R.P., Mitchell, R.H. (2003): The crystal structure of shcherbakovite from the Khibina Massif, Kola Peninsula, Russia. Canadian Mineralogist, 41, 1193-1201.

Of the last reference see the abstract:
The crystal structure of shcherbakovite from Mount Rasvumchorr, Khibina massif, Kola Peninsula, Russia, ideally K2 Na Ti24+ O (OH) [Si4O12], a 8.1538(4), b 10.5569(5), c 13.9882(6) Å, V 1204.1(2) Å3, space group Imma, Z = 4, Dcalc 3.194 g/cm3, has been refined to R1 = 3.2% for 960 unique (Fo > 4F) reflections collected on a Bruker single-crystal P4 diffractometer equipped with a CCD detector and MoK X-radiation. Shcherbakovite occurs in late (hydrothermal) shallowly dipping veins of natrolite and is associated with natrolite, aegirine, K-feldspar, strontian apatite, titanite, spherulitic baryllite and rare pyrrhotite and chalcopyrite. Electron-microprobe analysis gave SiO2 40.57, TiO2 18.87, Fe2O3 1.05, MnO 0.06, BaO 6.7, CaO 0.20, K2O 13.22, Na2O 5.59, Nb2O5 10.49, SrO 0.08, ZrO2 0.84, Ta2O5 0.06, (H2O)calc 0.73, sum 97.83 wt.%. The amount of H2O was determined from crystal-structure analysis. There is one tetrahedrally coordinated T site, <T–O> 1.607 Å, occupied by Si. There are two octahedrally coordinated sites, M(1), occupied by (Ti0.68 Nb0.32 1.00), with <M(1)–O> = 2.016 Å, and M(2), occupied by (Ti0.72 Nb0.15 Fe0.083+ Zr0.04 1.01), with <M(2)–O> = 1.999 Å. The M(1) and M(2) sites are separated by 0.477 Å, and hence cannot be occupied simultaneously at a local level. There are three interstitial A sites: the A(1) site is [9]-coordinated and is occupied by (K0.66 Ba0.23 Na0.07 Ca0.02), with <A(1)–O> = 2.952 Å; the A(2) site is [8]-coordinated and is occupied by K, with <A(2)–O> = 2.861 Å, and the A(3) site is [6]-coordinated and is occupied by Na, with <A(3)–O> = 2.493 Å. Shcherbakovite is a K-analogue of batisite, ideally Ba Na2 Ti24+ O2 [Si4O12]. Shcherbakovite is related to batisite by substitution of K for Ba and K for Na. "Noonkanbahite", ideally Ba K Na Ti24+ O2 [Si4O12], has never been approved by the IMA as a new mineral species. Based on the crystal chemistry of this structure type, the general formula of these minerals may be written as A B C M2 2 [Si4O12], with the following end-member compositions: batisite A = Ba, B = Na, C = Na; shcherbakovite, A = K, B = K, C = Na; "noonkanbahite", A = Ba, B = K, C = Na; unnamed, A = K, B = Na, C = Na.



Edited 1 time(s). Last edit at 11/09/2009 09:24AM by Marco E. Ciriotti.

IMA 2009-059 is also present in the Leucite Hills of Wyoming. According to Mitchell and Bergmann's "Petrology of Lamproites" analyses, all the Shcherbakovites from the Leucite Hills are probably IMA 2009-059.

Etienne