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Eskolaite

Big Photo

Outokumpu Cu-Co-Zn-Ni-Ag-Au ore field, Itä-Suomen Lääni, Finland
© 2004 M. Kampf

Formula:
Cr
 
2
O
 
3
System:TrigonalColour:Black
Hardness:8 - 8½
Name:After Professor Pentti Eelis Eskola (1883–1964), University of Helsinki, Helsinki, Finland.


Hematite Group.
The chromium analogue of Corundum, Hematite, and Karelianite.

Classification of Eskolaite

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:4/C.04-30
Nickel-Strunz 10th (pending) edition ID:4.CB.05

4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
C : Metal: Oxygen = 2: 3,3: 5, and similar
B : With medium-sized cations
Dana 8th edition ID:4.3.1.3

4 : SIMPLE OXIDES
3 : A2X3
Hey's CIM Ref.:7.14.1

7 : Oxides and Hydroxides
14 : Oxides of Cr
mindat.org URL:http://www.mindat.org/min-1411.html
Please feel free to link to this page.

Type Occurrence of Eskolaite

Type Locality:Outokumpu Cu-Co-Zn-Ni-Ag-Au ore field, Itä-Suomen Lääni, Finland
Year of Discovery:1958

Physical Properties of Eskolaite

Lustre:Metallic
Colour:Black
Streak:Green
Hardness (Mohs):8 - 8½

Crystallography of Eskolaite

Crystal System:Trigonal
Cell Parameters:a = 4.95Å, c = 13.58Å
Ratio:a:c = 1 : 2.743
Unit Cell Volume:V 288.16 ų (Calculated from Unit Cell)

Chemical Properties of Eskolaite

Formula:
Cr
 
2
O
 
3
Essential elements:Cr, O
All elements listed in formula:Cr, O
Common Impurities:V

Relationship of Eskolaite to other Species

Series:Forms a series with Karelianite (see here)
Member of Group:
Hematite Group:
M
 
2
O
 
3
Related Minerals - Nickel-Strunz Grouping):

- +
4.CB.05Brizziite
NaSb
5+
 
O
 
3
4.CB.05Corundum
Al
 
2
O
 
3
4.CB.05Ecandrewsite
(Zn,Fe
2+
 
,Mn
2+
 
)TiO
 
3
4.CB.05Geikielite
MgTiO
 
3
4.CB.05Hematite
Fe
 
2
O
 
3
4.CB.05Ilmenite
Fe
2+
 
TiO
 
3
4.CB.05Karelianite
V
 
2
O
 
3
4.CB.05Melanostibite
Mn
2+
 
(Sb
5+
 
,Fe
3+
 
)O
 
3
4.CB.05Pyrophanite
Mn
2+
 
TiO
 
3
4.CB.05Akimotoite
(Mg,Fe
2+
 
)SiO
 
3
4.CB.05Auroantimonate
AuSbO
 
3
4.CB.05Romanite
([],Pb,Ca)UFe
2+
2
(Ti,Fe
3+
 
)
 
6
Ti
 
12
O
 
38
4.CB.05UM1998-11-O-AuHSb
Au
 
2
SbO
 
2
(OH)
4.CB.05Tistarite
Ti
 
2
O
 
3
4.CB.10Avicennite
Tl
 
2
O
 
3
4.CB.10Bixbyite
(Mn
3+
 
,Fe
3+
 
)
 
2
O
 
3
4.CB.15Armalcolite
(Mg,Fe
2+
 
)Ti
 
2
O
 
5
4.CB.15Pseudobrookite
Fe
 
2
TiO
 
5
4.CB.15Mongshanite
(Mg,Cr,Fe
2+
 
)
 
2
(Ti,Zr)
 
5
O
 
12
4.CB.20Zincohögbomite-2N2S
(Zn,Al,Fe)
 
2
(Al,Fe,Ti)
 
8
O
 
15
(OH)
4.CB.20Zincohögbomite-2N6S
(Zn,Al)
 
7
(Al,Fe,Ti,Mg)
 
16
O
 
31
(OH)
4.CB.20Magnesiohögbomite-6N6S
(Mg,Al,Fe)
 
2
(Al,Ti)
 
8
O
 
15
(OH)
4.CB.20Magnesiohögbomite-2N3S
(Mg,Fe,Zn,Ti)
 
3
(Al,Fe)
 
10
O
 
19
(OH)
4.CB.20Magnesiohögbomite-2N2S
(Mg,Al,Fe)
 
2
(Al,Fe,Ti)
 
8
O
 
15
(OH)
4.CB.20Ferrohögbomite-6N12S
(Fe,Mg,Zn)
 
4
(Al,Ti,Fe)
 
12
O
 
23
(OH)
4.CB.25Pseudorutile
Fe
 
2
Ti
 
3
O
 
9
4.CB.30Berdesinskiite
V
3+
2
TiO
 
5
4.CB.30Oxyvanite
V
 
3
O
 
5
4.CB.35Olkhonskite
(Cr,V)
 
2
Ti
 
3
O
 
9
4.CB.35Schreyerite
V
 
2
Ti
 
3
O
 
9
4.CB.40Kamiokite
Fe
 
2
Mo
 
3
O
 
8
4.CB.40Nolanite
(V,Fe,Fe,Ti)
 
10
O
 
14
(OH)
 
2
4.CB.40Rinmanite
Zn
 
2
Sb
 
2
Mg
 
2
Fe
 
4
O
 
14
(OH)
 
2
4.CB.45Claudetite
As
 
2
O
 
3
4.CB.45Stibioclaudetite
AsSbO
 
3
4.CB.50Arsenolite
As
 
2
O
 
3
4.CB.50Sénarmontite
Sb
 
2
O
 
3
4.CB.55Valentinite
Sb
 
2
O
 
3
4.CB.60Bismite
Bi
 
2
O
 
3
4.CB.65Sphaerobismoite
Bi
 
2
O
 
3
4.CB.70Sillénite
Bi
 
12
SiO
 
20
4.CB.75Kyzylkumite
V
 
2
Ti
 
3
O
 
9
4.CB.80Tietaiyangite
Fe
3+
4
Fe
2+
 
TiO
 
9
Related Minerals - Hey's Index Grouping:

- +
7.14.2Bracewellite
CrO(OH)
7.14.3Grimaldiite
CrO(OH)
7.14.4Guyanaite
CrO(OH)
7.14.5Yimengite
K(Cr,Ti,Fe,Mg)
 
12
O
 
19
7.14.6Mathiasite
K(Ti,Cr,Fe,Mg,Zr)
 
21
O
 
38
7.14.7Mcconnellite
CuCrO
 
2
7.14.8Redledgeite
Ba
 
x
([Cr,Fe,V]
3+
2x
Ti
 
8-2x
)O
 
16
7.14.9Hawthorneite
BaMgTi
 
3
Cr
 
4
Fe
 
4
O
 
19
7.14.10Zincochromite
ZnCr
 
2
O
 
4
7.14.11Wattersite
(Hg-Hg)
2+
2
Hg
2+
 
[O
 
2
|CrO
 
4
]
7.14.12Chromite
FeCr
 
2
O
 
4
7.14.13Magnesiochromite
MgCr
 
2
O
 
4
7.14.14 Donathite

Other Names for Eskolaite

Other Languages:
German:Eskolait
Russian:Эсколаит
Spanish:Eskolaita

Other Information

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

References for Eskolaite

Reference List:American Mineralogist: 43: 1098-1106.

Zeitschrift für Kristallographie: 117: 233-237.

Internet Links for Eskolaite

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    Localities for Eskolaite

    Hide Locality List
    The 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.
    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Brazil
     
    • Northeast Region
      • Bahia
        • Érico Cardoso (old Água Quente)
          • Paramirim das Crioulas
    		Anthony, J. W. et al. (1997): Handbook of Mineralogy, Vol. 3, 33
    Jeannine and Jacques Cassedanne : "Présence d'eskolaite dans les alluvions stannifères de la Chapada Diamantina (Bahia-Brésil), Bull. Mineral., 1980, 103, pp 600-602.
        • Paramirim
    		[MinRec 16:111]
    Finland
     
    • Itä-Suomen Lääni
    		Am Min 43 (1958), 1098
    Guyana
     
    • Mazaruni District
      • Kamakusa
    		MINERALOGICAL MAGAZINE, DECEMBER 1984, VOL. 48, PP. 560 2
    Ireland
     
    • Co. Wicklow
      • Newton Mt. Kennedy
    		Mineralogical Magazine 1977 41 : 402-403
    Oman
     
    • Dhofar (Al Janubiyah) Province
    Russia
     
    • Eastern-Siberian Region
      • Prebaikalia (Pribaikal'e)
        • Irkutskaya Oblast'
          • Lake Baikal area
    		[MinRec 27:304]; Pekov, I. (1998) Minerals First discovered on the territory of the former Soviet Union 369p. Ocean Pictures, Moscow
            • Slyudyanka (Sludyanka)
    		Pekov, I. (1998) Minerals First discovered on the territory of the former Soviet Union 369p. Ocean Pictures, Moscow
              • Pokhabikha River Valley
    		Pekov, I. (1998) Minerals First discovered on the territory of the former Soviet Union 369p. Ocean Pictures, Moscow
    • Northern Region
      • Murmanskaja Oblast'
        • Kola Peninsula
    		www.koeln.netsurf.de/~w.steffens/khib.htm
    USA
     
    • California
      • San Benito Co.
        • Diablo Range
          • New Idria District
    		Dunning, Hadley, Cooper, Magnasco collections
    Mineral and/or Locality
    Google
     
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    Copyright © Jolyon Ralph and Ida Chau 1993-2009. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them.Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. If you would like to add information to improve the quality of our database, then click here to register. Current server date and time: 13th Nov 2009 21:45:22