JANCHEVITE, Pb7V(O8.5vac0.5)Cl2, A NEW MINERAL FROM THE KOMBAT MINE, NAMIBIA

N.V. Chukanov, D.O. Nekrasova, O.I. Siidra, Y.S. Polekhovsky, I.V. Pekov

Research output

1 Citation (Scopus)

Abstract

The new mineral janchevite was discovered in Mn-oxide ore from the Kombat mine, Grootfontein district, Otjozondjupa region, Namibia. Associated minerals are baryte, hausmannite, calcite, magnesite, and kombatite. Janchevite forms orange-red thick tabular anhedral to subhedral grains up to 0.4×0.8×0.8 mm in size. The luster is adamantine. The mineral is brittle, with Mohs' hardness of 2. Distinct cleavage on {001} is observed. D calc = 8.16 g/cm 3. The reflectance values [R max/R min, % (λ, nm)] are: 20.56/20.06 (470), 19.20/18.81 (546), 19.06/18.59 (589), 19.31/18.85 (650). An infrared spectrum indicates the absence of H-bearing groups and indicates V and Mo valences of 5+ and 6+, respectively. The chemical composition is (electron microprobe, wt.%): PbO 91.64, SiO 2 0.45, V 2O 5 1.95, MoO 3 2.41, Cl 4.16, -O=Cl .0.94, total 99.67. The empirical formula based on (Pb+V+Mo+Si)=8 apfu is Pb 7.20V 5+ 0.38Mo 6+ 0.29Si 0.13Cl 2.06O 8.25. Janchevite is the V-dominant analogue of parkinsonite. The mineral is tetragonal and its unit-cell parameters as determined from single-crystal X-ray diffraction data are: a 3.9591(5), c 22.6897(3) Å, V 355.65(1) Å 3; Z=1. Powder X-ray diffraction data conform to the space group I4/mmm; the strongest lines of the PXRD pattern [d, Å (I/I0, %) (hkl)] are: 3.889 (24) (011), 3.501 (31) (013), 2.979 (86) (015), 2.833 (25) (008), 2.794 (100) (110), 1.992 (26) (118), 1.988 (49) (020), 1.649 (46) (215). Janchevite is named in honor of the prominent Macedonian mineralogist Prof. Dr. Simeon Janchev (b. 1942).

Original languageEnglish
Pages (from-to)159-165
Number of pages7
JournalCanadian Mineralogist
Volume56
Issue number2
DOIs
Publication statusPublished - 31 Mar 2018

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new mineral
Minerals
mineral
X-ray diffraction
Bearings (structural)
magnesite
electron probe analysis
cleavage
hardness
Calcium Carbonate
reflectance
calcite
chemical composition
oxide
X ray powder diffraction
crystal
Oxides
Ores
Hardness
Single crystals

Scopus subject areas

  • Geochemistry and Petrology

Cite this

Chukanov, N.V. ; Nekrasova, D.O. ; Siidra, O.I. ; Polekhovsky, Y.S. ; Pekov, I.V. / JANCHEVITE, Pb7V(O8.5vac0.5)Cl2, A NEW MINERAL FROM THE KOMBAT MINE, NAMIBIA. In: Canadian Mineralogist. 2018 ; Vol. 56, No. 2. pp. 159-165.
@article{1f8cf21fa42c495789c1b63a5c3afcba,
title = "JANCHEVITE, Pb7V(O8.5vac0.5)Cl2, A NEW MINERAL FROM THE KOMBAT MINE, NAMIBIA",
abstract = "The new mineral janchevite was discovered in Mn-oxide ore from the Kombat mine, Grootfontein district, Otjozondjupa region, Namibia. Associated minerals are baryte, hausmannite, calcite, magnesite, and kombatite. Janchevite forms orange-red thick tabular anhedral to subhedral grains up to 0.4×0.8×0.8 mm in size. The luster is adamantine. The mineral is brittle, with Mohs' hardness of 2. Distinct cleavage on {001} is observed. D calc = 8.16 g/cm 3. The reflectance values [R max/R min, {\%} (λ, nm)] are: 20.56/20.06 (470), 19.20/18.81 (546), 19.06/18.59 (589), 19.31/18.85 (650). An infrared spectrum indicates the absence of H-bearing groups and indicates V and Mo valences of 5+ and 6+, respectively. The chemical composition is (electron microprobe, wt.{\%}): PbO 91.64, SiO 2 0.45, V 2O 5 1.95, MoO 3 2.41, Cl 4.16, -O=Cl .0.94, total 99.67. The empirical formula based on (Pb+V+Mo+Si)=8 apfu is Pb 7.20V 5+ 0.38Mo 6+ 0.29Si 0.13Cl 2.06O 8.25. Janchevite is the V-dominant analogue of parkinsonite. The mineral is tetragonal and its unit-cell parameters as determined from single-crystal X-ray diffraction data are: a 3.9591(5), c 22.6897(3) {\AA}, V 355.65(1) {\AA} 3; Z=1. Powder X-ray diffraction data conform to the space group I4/mmm; the strongest lines of the PXRD pattern [d, {\AA} (I/I0, {\%}) (hkl)] are: 3.889 (24) (011), 3.501 (31) (013), 2.979 (86) (015), 2.833 (25) (008), 2.794 (100) (110), 1.992 (26) (118), 1.988 (49) (020), 1.649 (46) (215). Janchevite is named in honor of the prominent Macedonian mineralogist Prof. Dr. Simeon Janchev (b. 1942).",
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author = "N.V. Chukanov and D.O. Nekrasova and O.I. Siidra and Y.S. Polekhovsky and I.V. Pekov",
year = "2018",
month = "3",
day = "31",
doi = "10.3749/canmin.1700081",
language = "English",
volume = "56",
pages = "159--165",
journal = "Canadian Mineralogist",
issn = "0008-4476",
publisher = "Mineralogical Association of Canada",
number = "2",

}

JANCHEVITE, Pb7V(O8.5vac0.5)Cl2, A NEW MINERAL FROM THE KOMBAT MINE, NAMIBIA. / Chukanov, N.V.; Nekrasova, D.O.; Siidra, O.I.; Polekhovsky, Y.S.; Pekov, I.V.

In: Canadian Mineralogist, Vol. 56, No. 2, 31.03.2018, p. 159-165.

Research output

TY - JOUR

T1 - JANCHEVITE, Pb7V(O8.5vac0.5)Cl2, A NEW MINERAL FROM THE KOMBAT MINE, NAMIBIA

AU - Chukanov, N.V.

AU - Nekrasova, D.O.

AU - Siidra, O.I.

AU - Polekhovsky, Y.S.

AU - Pekov, I.V.

PY - 2018/3/31

Y1 - 2018/3/31

N2 - The new mineral janchevite was discovered in Mn-oxide ore from the Kombat mine, Grootfontein district, Otjozondjupa region, Namibia. Associated minerals are baryte, hausmannite, calcite, magnesite, and kombatite. Janchevite forms orange-red thick tabular anhedral to subhedral grains up to 0.4×0.8×0.8 mm in size. The luster is adamantine. The mineral is brittle, with Mohs' hardness of 2. Distinct cleavage on {001} is observed. D calc = 8.16 g/cm 3. The reflectance values [R max/R min, % (λ, nm)] are: 20.56/20.06 (470), 19.20/18.81 (546), 19.06/18.59 (589), 19.31/18.85 (650). An infrared spectrum indicates the absence of H-bearing groups and indicates V and Mo valences of 5+ and 6+, respectively. The chemical composition is (electron microprobe, wt.%): PbO 91.64, SiO 2 0.45, V 2O 5 1.95, MoO 3 2.41, Cl 4.16, -O=Cl .0.94, total 99.67. The empirical formula based on (Pb+V+Mo+Si)=8 apfu is Pb 7.20V 5+ 0.38Mo 6+ 0.29Si 0.13Cl 2.06O 8.25. Janchevite is the V-dominant analogue of parkinsonite. The mineral is tetragonal and its unit-cell parameters as determined from single-crystal X-ray diffraction data are: a 3.9591(5), c 22.6897(3) Å, V 355.65(1) Å 3; Z=1. Powder X-ray diffraction data conform to the space group I4/mmm; the strongest lines of the PXRD pattern [d, Å (I/I0, %) (hkl)] are: 3.889 (24) (011), 3.501 (31) (013), 2.979 (86) (015), 2.833 (25) (008), 2.794 (100) (110), 1.992 (26) (118), 1.988 (49) (020), 1.649 (46) (215). Janchevite is named in honor of the prominent Macedonian mineralogist Prof. Dr. Simeon Janchev (b. 1942).

AB - The new mineral janchevite was discovered in Mn-oxide ore from the Kombat mine, Grootfontein district, Otjozondjupa region, Namibia. Associated minerals are baryte, hausmannite, calcite, magnesite, and kombatite. Janchevite forms orange-red thick tabular anhedral to subhedral grains up to 0.4×0.8×0.8 mm in size. The luster is adamantine. The mineral is brittle, with Mohs' hardness of 2. Distinct cleavage on {001} is observed. D calc = 8.16 g/cm 3. The reflectance values [R max/R min, % (λ, nm)] are: 20.56/20.06 (470), 19.20/18.81 (546), 19.06/18.59 (589), 19.31/18.85 (650). An infrared spectrum indicates the absence of H-bearing groups and indicates V and Mo valences of 5+ and 6+, respectively. The chemical composition is (electron microprobe, wt.%): PbO 91.64, SiO 2 0.45, V 2O 5 1.95, MoO 3 2.41, Cl 4.16, -O=Cl .0.94, total 99.67. The empirical formula based on (Pb+V+Mo+Si)=8 apfu is Pb 7.20V 5+ 0.38Mo 6+ 0.29Si 0.13Cl 2.06O 8.25. Janchevite is the V-dominant analogue of parkinsonite. The mineral is tetragonal and its unit-cell parameters as determined from single-crystal X-ray diffraction data are: a 3.9591(5), c 22.6897(3) Å, V 355.65(1) Å 3; Z=1. Powder X-ray diffraction data conform to the space group I4/mmm; the strongest lines of the PXRD pattern [d, Å (I/I0, %) (hkl)] are: 3.889 (24) (011), 3.501 (31) (013), 2.979 (86) (015), 2.833 (25) (008), 2.794 (100) (110), 1.992 (26) (118), 1.988 (49) (020), 1.649 (46) (215). Janchevite is named in honor of the prominent Macedonian mineralogist Prof. Dr. Simeon Janchev (b. 1942).

KW - Janchevite

KW - Kombat mine

KW - Lead vanadate oxychloride

KW - Namibia

KW - New mineral

KW - ANALOG

KW - lead vanadate oxychloride

KW - CRYSTAL-STRUCTURE

KW - PB OXYCHLORIDE MINERALS

KW - new mineral

KW - janchevite

KW - PARKINSONITE

KW - SAHLINITE

KW - CHEMISTRY

KW - ASISITE

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UR - http://www.canmin.org/lookup/doi/10.3749/canmin.1700081

UR - http://www.mendeley.com/research/janchevite-pb-sub7sub-v-sup5sup-o-sub85sub-sub05sub-cl-sub2sub-new-mineral-kombat-mine-namibia

U2 - 10.3749/canmin.1700081

DO - 10.3749/canmin.1700081

M3 - Article

VL - 56

SP - 159

EP - 165

JO - Canadian Mineralogist

JF - Canadian Mineralogist

SN - 0008-4476

IS - 2

ER -