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Otwayite

A valid IMA mineral species
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About OtwayiteHide

Formula:
Ni2(CO3)(OH)2 · H2O
Colour:
Green, bright green
Lustre:
Waxy, Silky
Hardness:
4
Specific Gravity:
3.41
Crystal System:
Orthorhombic
Name:
Named in 1977 by Ernest H. Nickel, Bruce W. Robinson, Charles E.S. Davis in honor of Mr. Charles Albert Otway (b. 1922) of Gosnells (Perth), Western Australia, a prospector and miner who held the mineral lease and provided samples of the mineral.
A mineral closely related to paraotwayite.


Unique IdentifiersHide

Mindat ID:
3044
Long-form identifier:
mindat:1:1:3044:7

IMA Classification of OtwayiteHide

Classification of OtwayiteHide

5.DA.15

5 : CARBONATES (NITRATES)
D : Carbonates with additional anions, with H2O
A : With medium-sized cations
16b.3.2.1

16b : HYDRATED CARBONATES CONTAINING HYDROXYL OR HALOGEN
3 : AmBn(XO3)pZqxH2O & with (m+n):p = 2:1
11.14.5

11 : Carbonates
14 : Carbonates of Co and Ni

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
OtwIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of OtwayiteHide

Waxy, Silky
Transparency:
Translucent, Opaque
Colour:
Green, bright green
Hardness:
Hardness:
VHN5=130 - 360 kg/mm2 - Vickers
Density:
3.41 g/cm3 (Measured)    3.346 g/cm3 (Calculated)

Optical Data of OtwayiteHide

Type:
Biaxial
RI values:
nα = 1.65 nγ = 1.72
Max. Birefringence:
δ = 0.070
Based on recorded range of RI values above.

Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.

Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.

Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.

Surface Relief:
Moderate
Dispersion:
very strong
Pleochroism:
Weak
Comments:
Deepest color normal to the fiber axis.

Chemistry of OtwayiteHide

Mindat Formula:
Ni2(CO3)(OH)2 · H2O
Element Weights:
Element% weight
Ni51.166 %
O41.842 %
C5.235 %
H1.757 %

Calculated from ideal end-member formula.
Common Impurities:
Mg

Crystallography of OtwayiteHide

Crystal System:
Orthorhombic
Cell Parameters:
a = 10.18 Å, b = 27.4 Å, c = 3.22 Å
Ratio:
a:b:c = 0.372 : 1 : 0.118
Unit Cell V:
898.2 ų
Z:
8
Comment:
Orthorhombic (?). Point Group: n.d.; Space Group: n.d.

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
6.84 Å(10)
5.67 Å(8)
2.737 Å(6)
3.022 Å(5)
2.529 Å(5)
2.24 Å(5)
2.370 Å(4)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 7: Great Oxidation Event<2.4
47a : [Near-surface hydration of prior minerals]
47c : [Carbonates, phosphates, borates, nitrates]

Type Occurrence of OtwayiteHide

General Appearance of Type Material:
Fibrous habit, rosette-like aggregates more or less normal to the veinlet walls.
Place of Conservation of Type Material:
Division of Mineralogy, CSIRO, Perth, Western Australia catalosue numbers 10016, 10027, and 10740.
Geological Setting of Type Material:
Narrow veinlets to 1 mm in width, probably late-stage fracture filling, transecting nickeloan serpentine, millerite, polydymite, and apatite.
Associated Minerals at Type Locality:

Synonyms of OtwayiteHide

Other Language Names for OtwayiteHide

Dutch:Otwayiet
German:Otwayit
Spanish:Otwayita

Common AssociatesHide

Associations Based on Photo Data:
1 photo of Otwayite associated with NullaginiteNi2(CO3)(OH)2
1 photo of Otwayite associated with WidgiemoolthaliteNi5(CO3)4(OH)2 · 5H2O

Related Minerals - Strunz-mindat GroupingHide

5.DA.AlexkhomyakoviteK6(Ca2Na)(CO3)5Cl · 6H2OHex. 6/mmm(6/m2/m2/m) : P63/mcm
5.DA.AmoraiteCa12Al6(OH)36(CO3)2(SO3) · 15H2O Tric. 1 : P1
5.DA.05DypingiteMg5(CO3)4(OH)2 · 5H2OMon. 2 : P21
5.DA.05'UM1986-10-CO:ClHMgMnZn (also called Mineral F, Dunn, 1995)'Mg5(Zn,Mn)3(CO3)2(OH,Cl)12 · H2O
5.DA.05'UM1987-01-CO:HMgS'Mg4(CO3)2(OH)4 · 6H2O ?Mon.
5.DA.05GiorgiositeMg5(CO3)4(OH)2 · 5-6H2O
5.DA.05HydromagnesiteMg5(CO3)4(OH)2 · 4H2OMon. 2/m : P21/b
5.DA.05WidgiemoolthaliteNi5(CO3)4(OH)2 · 5H2OMon. 2/m : P21/b
5.DA.10ArtiniteMg2(CO3)(OH)2 · 3H2OMon. 2/m : B2/m
5.DA.10ChlorartiniteMg2(CO3)(OH)Cl · 2H2OTrig. 3m : R3c
5.DA.10IndigiriteMg2Al2(CO3)4(OH)2 · 15H2O
5.DA.15ZaratiteNi3(CO3)(OH)4 · 4H2O ?Iso.
5.DA.20KambaldaiteNaNi4(CO3)3(OH)3 · 3H2OHex. 6 : P63
5.DA.25CallaghaniteCu2Mg2(CO3)(OH)6 · 2H2OMon. 2/m : B2/b
5.DA.30Claraite(Cu,Zn)15(CO3)4(AsO4)2(SO4)(OH)14 · 7H2OTric. 1 : P1
5.DA.35HydroscarbroiteAl14(CO3)3(OH)36 · nH2OTric.
5.DA.35ScarbroiteAl5(CO3)(OH)13 · 5H2OTric.
5.DA.40KarchevskyiteMg18Al9(OH)54Sr2(CO3)9(H2O)6(H3O)5Trig.
5.DA.40'UM1987-05-OH:AlCMg'Mg4Al2(OH)12(CO3,SO4) · 3H2O
5.DA.40QuintiniteMg4Al2(OH)12(CO3) · 3H2OHex. 622 : P6322
5.DA.40CharmariteMn2+4Al2(OH)12[CO3] · 3H2OHex.
5.DA.40CaresiteFe2+4Al2(OH)12[CO3] · 3H2OTrig. 32 : P3112
5.DA.45'Hydrotalcite-2H'Mg6Al2(CO3)(OH)16 · 4H2OHex. 6/mmm(6/m2/m2/m) : P63/mmc
5.DA.45'Stichtite-2H'Mg6(Cr,Al)2(CO3)(OH)16 · 4H2OHex. 6/mmm(6/m2/m2/m) : P63/mmc
5.DA.45BrugnatelliteMg6Fe3+(CO3)(OH)13 · 4H2OHex.
5.DA.45ZaccagnaiteZn4Al2(OH)12[CO3] · 3H2OHex.
5.DA.45'Pyroaurite-2H'Mg6Fe3+2(OH)16(CO3) · 4H2OHex. 6/mmm(6/m2/m2/m) : P63/mmc
5.DA.45LiudongshengiteZn4Cr2(OH)12(CO3) · 3H2OTrig. 3m(32/m) : R3m
5.DA.45ChlormagaluminiteMg4Al2(OH)12Cl2 · 3H2OHex. 6/mmm(6/m2/m2/m) : P63/mcm
5.DA.50PyroauriteMg6Fe3+2(OH)16[CO3] · 4H2OTrig. 3m(32/m) : R3m
5.DA.50TakoviteNi6Al2(OH)16[CO3] · 4H2OTrig. 3m(32/m) : R3m
5.DA.50ReevesiteNi6Fe3+2(OH)16(CO3) · 4H2OTrig. 3m(32/m) : R3m
5.DA.50KaznakhtiteNi6Co3+2(CO3)(OH)16 · 4H2OTrig. 3 : R3
5.DA.50ComblainiteNi4Co2(OH)12[CO3] · 3H2OTrig.
5.DA.50Marioantofilliite[Cu4Al2(OH)12](CO3) · 3H2OMon. 2/m : B2/m
5.DA.50HydrotalciteMg6Al2(CO3)(OH)16 · 4H2OTrig. 3m(32/m) : R3m
5.DA.50StichtiteMg6Cr3+2(OH)16[CO3] · 4H2OTrig. 3m(32/m) : R3m
5.DA.50DesautelsiteMg6Mn3+2(OH)16[CO3] · 4H2OTrig. 3m(32/m)
5.DA.55CoalingiteMg10Fe3+2(OH)24[CO3] · 2H2OTrig. 3m(32/m) : R3m
5.DA.55Akopovaite Al4Li2(OH)12(CO3)(H2O)3Mon. 2/m : B2/m
5.DA.60ŠlikiteZn2Mg(CO3)2(OH)2 · 4H2OTric. 1 : P1
5.DA.65MarkliteCu5(CO3)2(OH)6 · 6H2OMon. 2/m : P21/b

Other InformationHide

Notes:
Dissolves slowly in cold 1:1 HCl; at 100 C it dissolves rapidly, with visible evolution of CO2 bubbles.
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 OtwayiteHide

References for OtwayiteHide

Localities for OtwayiteHide

Showing 8 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.
Australia
 
  • Tasmania
    • Waratah-Wynyard municipality
      • Heazlewood district
Witzke et al. (2022) +2 other references
  • Western Australia
    • Coolgardie Shire
Naldrett (2004)
      • Widgiemooltha
Nickel et al. (1993) +1 other reference
    • East Pilbara Shire
      • Nullagine
Nickel +3 other references
Greece
 
  • Central Macedonia
Shen (n.d.)
South Africa
 
  • Limpopo
    • Vhembe District Municipality
      • Musina Local Municipality
Cairncross et al. (1995)
Cairncross et al. (1995)
Spain
 
  • Catalonia
    • Tarragona
      • Priorat
        • Bellmunt del Priorat
Joan Abella i Creus: ... +1 other reference
 
and/or  
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