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Jacobsite-Q

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05324070017360473804073.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
08066980017272039476555.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
09632630017360473822085.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
04137600017271924075836.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
04325880017271924115943.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
09632630017360473822085.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
04137600017271924075836.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
04325880017271924115943.jpg
Jacobsite-Q, etc.

Gozaisho Mine, Iwaki City, Fukushima Prefecture, Japan
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About Jacobsite-QHide

Formula:
Mn2+(Fe3+,Mn3+)2O4
From Bosi et al. (2018); type material has Fe3+:Mn3+ = 2:1.
Colour:
Greenish black, black
Lustre:
Sub-Vitreous, Metallic, Sub-Metallic
Hardness:
6 - 6½
Specific Gravity:
4.85
Crystal System:
Tetragonal
Dimorph of:
Jacobsite
Isostructural with:
Spinel
A polymorph of jacobsite, termed jacobsite-Q, earlier named iwakiite.
Contains significant octahedrally coordinated Mn3+ distorting the crystal structure to tetragonal.

See also α-vredenburgite.


Unique IdentifiersHide

Mindat ID:
2058
Long-form identifier:
mindat:1:1:2058:5

Similar NamesHide

JacobsiteA valid IMA mineral species - grandfatheredMn2+Fe23+O4

IMA Classification of Jacobsite-QHide

IMA status notes:
Redefined by the IMA, Renamed by the IMA
Approval history:
First described as iwakiite by Matsurbara et al. (1979). Redefined as the tetragonal polymorph of jacobsite and renamed as jacobsite-Q by IMA 2018 (Bosi et al. 2018).

Classification of Jacobsite-QHide

Dana 8th ed.:
7.2.6.2

7 : MULTIPLE OXIDES
2 : AB2X4
Hey's CIM Ref.:
7.9.14

7 : Oxides and Hydroxides
9 : Oxides of Ti

Physical Properties of Jacobsite-QHide

Lustre:
Sub-Vitreous, Metallic, Sub-Metallic
Transparency:
Opaque
Colour:
Greenish black, black
Comment:
May look completely black, may be iridescent due to surface alteration.
Streak:
Black
Hardness:
6 - 6½ on Mohs scale
Tenacity:
Brittle
Cleavage:
None Observed
None
Fracture:
Conchoidal, Sub-Conchoidal
Density:
4.85 g/cm3 (Measured)    4.89 g/cm3 (Calculated)

Optical Data of Jacobsite-QHide

Reflectivity:
WavelengthR1 (%)
20nm20 20.0 19.4440 19.9 19.3460 20.3 19.5480 20.4 19.6500 20.8 19.8520 21.2 20.1540 21.4 20.3560 21.3 20.4580 21.2 20.1600 21.0 20.0620 20.9 19.7640 20.5 19.6660 20.4 19.2680 20.2 19.1%


Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 20 20.0 19.4440 19.9 19.3460 20.3 19.5480 20.4 19.6500 20.8 19.8520 21.2 20.1540 21.4 20.3560 21.3 20.4580 21.2 20.1600 21.0 20.0620 20.9 19.7640 20.5 19.6660 20.4 19.2680 20.2 19.1%.
Colour in reflected light:
olive-gray
Internal Reflections:
none observed
Pleochroism:
Non-pleochroic

Chemistry of Jacobsite-QHide

Mindat Formula:
Mn2+(Fe3+,Mn3+)2O4

From Bosi et al. (2018); type material has Fe3+:Mn3+ = 2:1.
Element Weights:
Element% weight
Fe48.429 %
O27.750 %
Mn23.821 %

Calculated from ideal end-member formula.
Elements listed:
Fe, Mn, O - search for minerals with similar chemistry

Crystallography of Jacobsite-QHide

Crystal System:
Tetragonal
Class (H-M):
4/mmm(4/m2/m2/m) - Ditetragonal Dipyramidal
Space Group:
I41/amd
Setting:
I41/amd
Cell Parameters:
a = 6.025 Å, c = 8.54 Å
Ratio:
a:c = 1 : 1.417
Unit Cell V:
310.01 ų (Calculated from Unit Cell)
Z:
4
Morphology:
Rarely octahedral, usually granular
Twinning:
{101}, similar to hausmannite

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0010983Jacobsite-QJarosch D (1988) Crystal structure of iwakiite Zeitschrift fur Kristallographie 185 605-6051988Gozaisho mine, Fukushima Prefecture, Japan0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
4.929 Å(30)
3.016 Å(40)
2.570 Å(100)
2.461 Å(6)
2.135 Å(16)
2.130 Å(16)
1.739 Å(15)
1.640 Å(30)
1.509 Å(35)
1.506 Å(40)
1.299 Å(10)
1.284 Å(8)
Comments:
Satoshi MATSUBARA, Akira KATO, Kozo NAGASHIMA (1978) Mineralogical Magazine, v9, pp.383-391.

First Recorded Occurrence of Jacobsite-QHide

Synonyms of Jacobsite-QHide

Other Language Names for Jacobsite-QHide

Relationship of Jacobsite-Q to other SpeciesHide

Member of:
Spinel Subgroup > Oxyspinel Group > Spinel Supergroup
Other Members of Spinel Subgroup:
ChihmingiteNiAl2O4Iso. m3m(4/m32/m) : Fd3m
ChromiteFe2+Cr3+2O4Iso. m3m(4/m32/m) : Fd3m
CochromiteCoCr2O4Iso. m3m(4/m32/m) : Fd3m
CoulsoniteFe2+V3+2O4Iso. m3m(4/m32/m) : Fd3m
CuprospinelCu2+Fe3+2O4Iso. m3m(4/m32/m) : Fd3m
DellagiustaiteV2+Al2O4Iso. m3m(4/m32/m) : Fd3m
Deltalumite(Al0.67◻0.33)Al2O4Tet. 42m : P4m2
FrankliniteZn2+Fe3+2O4Iso. m3m(4/m32/m) : Fd3m
GahniteZnAl2O4Iso. m3m(4/m32/m) : Fd3m
GalaxiteMn2+Al2O4Iso. m3m(4/m32/m) : Fd3m
GuiteCo2+Co3+2O4Iso.
HausmanniteMn2+Mn3+2O4Tet. 4/mmm(4/m2/m2/m) : I41/amd
HercyniteFe2+Al2O4Iso. m3m(4/m32/m) : Fd3m
HetaeroliteZnMn2O4Tet. 4/mmm(4/m2/m2/m) : I41/amd
JacobsiteMn2+Fe3+2O4Iso. m3m(4/m32/m) : Fd3m
Maghemite(Fe3+0.67◻0.33)Fe3+2O4Iso. 432 : P4132
MagnesiochromiteMgCr2O4Iso. m3m(4/m32/m) : Fd3m
MagnesiocoulsoniteMgV2O4Iso. m3m(4/m32/m)
MagnesioferriteMgFe3+2O4Iso. m3m(4/m32/m) : Fd3m
MagnetiteFe2+Fe3+2O4Iso. m3m(4/m32/m) : Fd3m
ManganochromiteMn2+Cr2O4Iso. m3m(4/m32/m) : Fd3m
'Nichromite'(Ni,Co,Fe)(Cr,Fe,Al)2O4Iso. m3m(4/m32/m) : Fd3m
SpinelMgAl2O4Iso. m3m(4/m32/m) : Fd3m
ThermaerogeniteCuAl2O4Iso. m3m(4/m32/m) : Fd3m
Titanomaghemite(Ti4+0.5◻0.5)Fe3+2O4Iso. 432 : P4332
TrevoriteNi2+Fe3+2O4Iso. m3m(4/m32/m) : Fd3m
'UM1994-06-O:AlCo'CoAl2O4
VuorelaineniteMn2+V3+2O4Iso. m3m(4/m32/m) : Fd3m
ZincochromiteZnCr2O4Iso. m3m(4/m32/m) : Fd3m

Common AssociatesHide

Associations Based on Photo Data:
2 photos of Jacobsite-Q associated with SpessartineMn2+3Al2(SiO4)3
1 photo of Jacobsite-Q associated with JacobsiteMn2+Fe3+2O4
1 photo of Jacobsite-Q associated with DiopsideCaMgSi2O6
1 photo of Jacobsite-Q associated with RhodoniteCaMn3Mn[Si5O15]
1 photo of Jacobsite-Q associated with CalciteCaCO3
1 photo of Jacobsite-Q associated with 'Manganophyllite'K(Fe,Mg,Mn)3AlSi3O10(OH)2
1 photo of Jacobsite-Q associated with AdeliteCaMg(AsO4)(OH)

Fluorescence of Jacobsite-QHide

In UV light:
Not fluorescent in UV

Other InformationHide

Magnetism:
Ferrimagnetic
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for Jacobsite-QHide

References for Jacobsite-QHide

Localities for Jacobsite-QHide

Showing 13 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Austria
 
  • Tyrol
    • Lienz District
      • PrĂ€graten am Großvenediger
        • Timmelbach valley
Kolitsch et al. (2017)
Japan (FRL)
 
  • Fukushima Prefecture
    • Iwaki City
Matsubara et al. (1979) +3 other references
Romania
 
  • Maramureș County
    • TĂąrgu Lăpuș
Udubasa et al. (1996) +2 other references
Slovakia
 
  • KoĆĄice Region
    • RoĆŸĆˆava District
      • Čučma
Radvanec M. and Gonda S. (2020)
Spain
 
  • Andalusia
    • AlmerĂ­a
      • Cuevas del Almanzora
        • Sierra Almagrera
Calvo Rebollar et al. (2022)
Sweden
 
  • Dalarna County
    • Hedemora
      • Garpenberg
Gatedal (n.d.) +1 other reference
  • Örebro County
    • HĂ€llefors
      • Grythyttan
Holtstam et al. (2001)
  • VĂ€rmland County
    • Filipstad
      • LĂ„ngban Ore District
Nysten (2014)
      • Nordmark mining district
        • Jakobsberg ore field
Gatedal (2003)
Gatedal (2003)
      • Persberg ore district
        • Pajsberg
Gatedal (2003) +1 other reference
UK
 
  • Wales
    • Gwynedd
      • Aberdaron
        • Rhiw
Cotterell (2008)
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