Škáchaite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Škáchaite
Formula:
CaCo(CO3)2
Colour:
Pale to bright pink
Lustre:
Vitreous
Hardness:
3½ - 4
Specific Gravity:
3.140 (Calculated)
Crystal System:
Trigonal
Member of:
Name:
After Pavel Škácha, Ph.D., Curator at the Mining Muzeum Příbram, Czech Republic.
The cobalt-dominant member of the group. The Co analogue of ankerite, dolomite, kutnohorite, and minrecordite. Unique combination of elements (2024).
Compare the varieties 'Cobalt-bearing Dolomite', Cobalt-bearing Calcite, Cobalt-bearing Calcite-Spherocobaltite and Cobalt-bearing Aragonite.
Compare the varieties 'Cobalt-bearing Dolomite', Cobalt-bearing Calcite, Cobalt-bearing Calcite-Spherocobaltite and Cobalt-bearing Aragonite.
Name Encoding
Latin-1:
Skáchaite
ASCII-7:
Skachaite
Unique Identifiers
Mindat ID:
470706
Long-form identifier:
mindat:1:1:470706:2
IMA Classification of Škáchaite
Approved
IMA Formula:
CaCo2+(CO3)2
Approval year:
2023
Classification of Škáchaite
5.AB.10
5 : CARBONATES (NITRATES)
A : Carbonates without additional anions, without H2O
B : Alkali-earth (and other M2+) carbonates
5 : CARBONATES (NITRATES)
A : Carbonates without additional anions, without H2O
B : Alkali-earth (and other M2+) carbonates
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Škác | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Škáchaite
Vitreous
Transparency:
Translucent
Colour:
Pale to bright pink
Streak:
White
Hardness:
3½ - 4 on Mohs scale
Tenacity:
Brittle
Cleavage:
Perfect
{1011}
{1011}
Density:
3.140 g/cm3 (Calculated)
Optical Data of Škáchaite
Type:
Uniaxial (-)
RI values:
nω = 1.741(3) nε = 1.535(3)
Max. Birefringence:
δ = 0.206
Based on recorded range of RI values above.
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.
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:
Very High (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).
Relative to Canada balsam mounting medium (n ≈ 1.537).
This shows the grain boundary and Becke line effect under plane-polarised
light, based on the contrast between this mineral's average refractive
index and the mounting medium. It does not take into account mineral
colouration.
In focus
Interference Figure:
This shows the idealized uniaxial interference figure - the conoscopic
(convergent-light, Bertrand-lens-in) view, for a grain cut with the optic axis
centred and vertical. The coloured rings are isochromatics, computed with the
same physics as the Michel-Lévy bar above; the dark cross is the isogyre.
For a genuinely uniaxial mineral viewed this way, that cross stays perfectly stationary if you rotate the stage - unlike a biaxial mineral, where it splits apart on rotation. That invariance is itself the standard diagnostic test for telling uniaxial and biaxial minerals apart at the microscope.
For a genuinely uniaxial mineral viewed this way, that cross stays perfectly stationary if you rotate the stage - unlike a biaxial mineral, where it splits apart on rotation. That invariance is itself the standard diagnostic test for telling uniaxial and biaxial minerals apart at the microscope.
Optical Extinction:
has hints of undulatory extinction
Pleochroism:
Non-pleochroic
Chemistry of Škáchaite
Mindat Formula:
CaCo(CO3)2
Element Weights:
Elements listed:
Crystallography of Škáchaite
Crystal System:
Trigonal
Class (H-M):
3 - Rhombohedral
Space Group:
R3
Cell Parameters:
a = 4.8177(18) Å, c = 16.093(7) Å
Ratio:
a:c = 1 : 3.34
Unit Cell V:
323.48 ų (Calculated from Unit Cell)
Z:
3
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 3.704 Å | (13) |
| 2.896 Å | (100) |
| 2.409 Å | (15) |
| 2.197 Å | (11) |
| 2.019 Å | (17) |
| 1.812 Å | (19) |
| 1.792 Å | (16) |
| 1.391 Å | (9) |
Type Occurrence of Škáchaite
General Appearance of Type Material:
Anhedral grains up to 50 μm in size and 20-100 μm thick growth zones in škáchaite-dolomite solid-solution crystals.
Place of Conservation of Type Material:
Collections of the Department of Mineralogy and Petrology, National Museum, Cirkusová 1740, 19300 Prague 9, Czech Republic, catalogue number P1P 52/2022
Geological Setting of Type Material:
Hydrothermal vein.
Associated Minerals at Type Locality:
Synonyms of Škáchaite
Other Language Names for Škáchaite
Relationship of Škáchaite to other Species
Member of:
Other Members of Dolomite Group:
| Ankerite | Ca(Fe2+,Mg)(CO3)2 | Trig. 3 : R3 |
| Dolomite | CaMg(CO3)2 | Trig. 3 : R3 |
| Kutnohorite | CaMn2+(CO3)2 | Trig. 3 : R3 |
| Minrecordite | CaZn(CO3)2 | Trig. 3 : R3 |
| Norsethite | BaMg(CO3)2 | Trig. 32 : R32 |
| 'Unnamed (Pb analogue of Dolomite)' | PbMg(CO3)2 |
Common Associates
Associations Based on Photo Data:
| 1 photo of Škáchaite associated with 'Cobalt-bearing Dolomite' | Ca(Mg,Co)(CO3)2 |
Related Minerals - Strunz-mindat Grouping
| 5.AB.05 | Siderite | FeCO3 |
| 5.AB.05 | Rhodochrosite | MnCO3 |
| 5.AB.05 | Calcite | CaCO3 |
| 5.AB.05 | Smithsonite | ZnCO3 |
| 5.AB.05 | Gaspéite | NiCO3 |
| 5.AB.05 | Spherocobaltite | CoCO3 |
| 5.AB.05 | Magnesite | MgCO3 |
| 5.AB.05 | Otavite | CdCO3 |
| 5.AB.05 va | 'Parakutnohorite' | |
| 5.AB.10 | Dolomite | CaMg(CO3)2 |
| 5.AB.10 | Minrecordite | CaZn(CO3)2 |
| 5.AB.10 | Ankerite | Ca(Fe2+,Mg)(CO3)2 |
| 5.AB.10 | Kutnohorite | CaMn2+(CO3)2 |
| 5.AB.15 | Aragonite | CaCO3 |
| 5.AB.15 | Cerussite | PbCO3 |
| 5.AB.15 | Witherite | BaCO3 |
| 5.AB.15 | Strontianite | SrCO3 |
| 5.AB.20 | Vaterite | CaCO3 |
| 5.AB.25 | Huntite | CaMg3(CO3)4 |
| 5.AB.30 | Norsethite | BaMg(CO3)2 |
| 5.AB.35 | Alstonite | BaCa(CO3)2 |
| 5.AB.40 | Paralstonite | BaCa(CO3)2 |
| 5.AB.40 | Olekminskite | Sr(Sr,Ca,Ba)(CO3)2 |
| 5.AB.45 | Barytocalcite | BaCa(CO3)2 |
| 5.AB.50 | Carbocernaite | (Ca,Na)(Sr,Ce,Ba)(CO3)2 |
| 5.AB.55 | Benstonite | Ba6Ca6Mg(CO3)13 |
| 5.AB.60 | Juangodoyite | Na2Cu(CO3)2 |
Fluorescence of Škáchaite
not fluoresce under either short- or long-wave ultraviolet light.
Other Information
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 Škáchaite
mindat.org URL:
https://www.mindat.org/min-470706.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Škáchaite
Localities for Škáchaite
Showing 1 localities.
symbol to view information about a locality.
The Locality List
- 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).
All localities listed without proper references should be considered as questionable.
Czech Republic (TL) | |
| Bosi et al. (2023) +1 other reference |
Quick NavTopAbout ŠkáchaiteName EncodingUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionType Occurrence SynonymsOther LanguagesRelationshipsCommon AssociatesStrunz-MindatFluorescence Other InformationInternet Links References Localities Locality List
B117 hydrothermal vein, Uranium Mine No. 6, Brod, Příbram, Příbram District, Central Bohemian Region, Czech Republic