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Nováčekite

A valid IMA mineral species - grandfathered
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About NováčekiteHide

05085480017272471844489.jpg
Radim Nováček
Formula:
Mg(UO2)2(AsO4)2 · 10H2O
Colour:
Pale yellow, yellow
Lustre:
Resinous, Waxy
Hardness:
2 - 2½
Specific Gravity:
3.25 - 3.70
Crystal System:
Monoclinic
Member of:
Name:
Named nováčekite in 1951 by Clifford Frondel in honor of Radim Nováček [March 21, 1905 Ústí Nad Orlicí, Bohemia, Austria-Hungary - February 12, 1942 Mauthausen, Austria] mineralogist and analytical chemist, Charles University, Prague, Czech Republic. Following persecution of the Czech intelligentsia under Nazi occupation, Radim Nováček became involved in resistance intelligence operations starting in 1939. He was ultimately arrested in October 1941, convicted of treason, and sent to the Mauthausen concentration camp where he was executed. Prior to his arrest, he had recruited fellow mineralogist Karel Tuček (tučekite) to the resistance.

This mineral was renamed to nováčekite-II with the Roman numerals indicating hydration/dehydration stages (Walenta 1964) and the diacritical marks were added in 2008 (Burke). Renamed to nováčekite (with diacritics and without Roman numerals) in 2022.
Isostructural with:
Formerly called nováčekite-II.
Chemically similar to metanováčekite (the lower hydrate), hydronováčekite (the higher hydrate) and seelite (an arsenite/arsenate).

Note: Hydronováčekite (formerly called nováčekite-I) is very unstable under ambient conditions and quickly dehydrates to nováčekite, in part also to metanováčekite (Walenta, 1964).
Nováčekite may also reversibly rehydrate from metanováčekite under ambient conditions.


Name EncodingHide

CP1252:
Novácekite
Latin-1:
Novácekite
ASCII-7:
Novacekite

Unique IdentifiersHide

Mindat ID:
39584
Long-form identifier:
mindat:1:1:39584:3

Similar NamesHide

Classification of NováčekiteHide

00572780017683530272384.jpg
The autunite-type sheet

The autunite-type sheet found in members of the autunite group.

IMA Classification of NováčekiteHide

Approved, 'Grandfathered' (first described prior to 1959)
IMA status notes:
Renamed by the IMA
IMA Formula:
Mg(U6+O2)2(As5+O4)2(H2O)10
First published:
1951
8.EB.05

8 : PHOSPHATES, ARSENATES, VANADATES
E : Uranyl phosphates and arsenates
B : UO2:RO4 = 1:1

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

Physical Properties of NováčekiteHide

Resinous, Waxy
Transparency:
Translucent
Colour:
Pale yellow, yellow
Streak:
Very pale yellow
Hardness:
2 - 2½ on Mohs scale
Tenacity:
Waxy
Cleavage:
Perfect
{001}
Fracture:
Micaceous
Density:
3.25 - 3.70 g/cm3 (Measured)    3.27 g/cm3 (Calculated)

Optical Data of NováčekiteHide

Type:
Biaxial (-)
RI values:
nα = 1.543 nβ = 1.570 nγ = 1.577 nω = 1.578 nε = 1.548
Birefringence:
0.032
Max. Birefringence:
δ = 0.034
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:
Low (positive)
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 biaxial acute bisectrix (Bxa) interference figure - the conoscopic view for a grain cut perpendicular to the acute bisectrix, using this mineral's 2V. The two small white dots mark the melatopes - the points where the two optic axes emerge - and are shown only when they fall within the field of view. The coloured bands are isochromatics, and the dark bands are isogyres.

Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.

No measured or calculated 2V is on file for this mineral, so the value used here (53°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
Dispersion:
r>v, strong
Pleochroism:
Visible
Comments:
X = nearly colorless, Y = Z = pale yellow to pale yellow green

Chemistry of NováčekiteHide

Mindat Formula:
Mg(UO2)2(AsO4)2 · 10H2O
Element Weights:
Element% weight
U46.565 %
O34.429 %
As14.657 %
Mg2.377 %
H1.972 %

Calculated from ideal end-member formula.
U
O
As
Mg
H

Crystallography of NováčekiteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/c
Setting:
P21/n
Cell Parameters:
a = 7.1328(11) Å, b = 20.085(3) Å, c = 7.1569(11) Å
β = 90.585(3)°
Ratio:
a:b:c = 0.355 : 1 : 0.356
Unit Cell V:
1,025.26 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Square tablets
Comment:
pseudotetragonal (pseudo-space group P42/n, a = 7.18-7.20 A, c = 20.16-20.22 A, Z = 2).

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
10.2 Å(100)
6.80 Å(40)
5.06 Å(80)
3.58 Å(90)
3.35 Å(50)
2.52 Å(30)
2.26 Å(30)

Geological EnvironmentHide

Synonyms of NováčekiteHide

Other Language Names for NováčekiteHide

Relationship of Nováčekite to other SpeciesHide

Member of:
Other Members of Autunite Group:
AutuniteCa(UO2)2(PO4)2 · 10-12H2OOrth. mmm(2/m2/m2/m) : Pnma
BassetiteFe2+(UO2)2(PO4)2 · 10H2OMon. 2/m : P21/c
HeinrichiteBa(UO2)2(AsO4)2 · 10H2OMon. 2/m : P2/b
HydronováčekiteMg(UO2)2(AsO4)2 · 12H2OTric. 1 : P1
KahleriteFe2+(UO2)2(AsO4)2 · 12H2OTet. 4/m : P42/n
RauchiteNi(UO2)2(AsO4)2 · 10H2OTric. 1 : P1
SabugaliteHAl(UO2)4(PO4)4 · 16H2OMon. 2/m : B2/m
SaléeiteMg(UO2)2(PO4)2 · 10H2OMon. 2/m : P21/c
TorberniteCu(UO2)2(PO4)2 · 12H2OTet. 4/mmm(4/m2/m2/m) : I4/mmm
UranocirciteBa(UO2)2(PO4)2 · 10H2OTet.
UranospiniteCa(UO2)2(AsO4)2 · 10H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
ZeuneriteCu(UO2)2(AsO4)2 · 12H2OTet. 4/mmm(4/m2/m2/m) : I4/mmm

Common AssociatesHide

Associations Based on Photo Data:
8 photos of Nováčekite associated with SklodowskiteMg(UO2)2(SiO3OH)2 · 6H2O
6 photos of Nováčekite associated with TyuyamuniteCa(UO2)2(VO4)2 · 5-8H2O
5 photos of Nováčekite associated with ZeuneriteCu(UO2)2(AsO4)2 · 12H2O
5 photos of Nováčekite associated with ErythriteCo3(AsO4)2 · 8H2O
5 photos of Nováčekite associated with AragoniteCaCO3
4 photos of Nováčekite associated with GypsumCaSO4 · 2H2O
3 photos of Nováčekite associated with Umohoite(UO2)MoO4 · 2H2O
3 photos of Nováčekite associated with QuartzSiO2
3 photos of Nováčekite associated with HematiteFe2O3
3 photos of Nováčekite associated with CalciteCaCO3

Related Minerals - Strunz-mindat GroupingHide

8.EB.Meta-autunite GroupA1-2(UO2)2(TO4)2 · 5-10H2O
8.EB.05RauchiteNi(UO2)2(AsO4)2 · 10H2OTric. 1 : P1
8.EB.05UranocirciteBa(UO2)2(PO4)2 · 10H2OTet.
8.EB.05UranospiniteCa(UO2)2(AsO4)2 · 10H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
8.EB.05ZeuneriteCu(UO2)2(AsO4)2 · 12H2OTet. 4/mmm(4/m2/m2/m) : I4/mmm
8.EB.05MetarauchiteNi(UO2)2(AsO4)2 · 8H2OTric. 1 : P1
8.EB.05HeinrichiteBa(UO2)2(AsO4)2 · 10H2OMon. 2/m : P2/b
8.EB.05KahleriteFe2+(UO2)2(AsO4)2 · 12H2OTet. 4/m : P42/n
8.EB.05HydronováčekiteMg(UO2)2(AsO4)2 · 12H2OTric. 1 : P1
8.EB.05TorberniteCu(UO2)2(PO4)2 · 12H2OTet. 4/mmm(4/m2/m2/m) : I4/mmm
8.EB.05AutuniteCa(UO2)2(PO4)2 · 10-12H2OOrth. mmm(2/m2/m2/m) : Pnma
8.EB.05SaléeiteMg(UO2)2(PO4)2 · 10H2OMon. 2/m : P21/c
8.EB.05Xiangjiangite(Fe3+,Al)(UO2)4(PO4)2(SO4)2(OH) · 22H2OTet.
8.EB.10BassetiteFe2+(UO2)2(PO4)2 · 10H2OMon. 2/m : P21/c
8.EB.10LehneriteMn2+(UO2)2(PO4)2 · 8H2OMon. 2/m : P21/c
8.EB.10Meta-autuniteCa(UO2)2(PO4)2 · 6H2OTet. 4/mmm(4/m2/m2/m)
8.EB.10MetasaléeiteMg(UO2)2(PO4)2 · 8H2O
8.EB.10MetauranocirciteBa(UO2)2(PO4)2 · 7H2OMon. 2 : P21
8.EB.10MetauranospiniteCa(UO2)2(AsO4)2 · 8H2OTet. 4/m : P42/n
8.EB.10MetaheinrichiteBa(UO2)2(AsO4)2 · 8H2OMon. 2 : P21
8.EB.10MetakahleriteFe2+(UO2)2(AsO4)2 · 8H2OTric. 1 : P1
8.EB.10MetakirchheimeriteCo(UO2)2(AsO4)2 · 8H2OTric. 1 : P1
8.EB.10MetanováčekiteMg(UO2)2(AsO4)2 · 8H2OTet. 4/m : P4/n
8.EB.10MetanatroautuniteNa(UO2)(PO4)(H2O)3Tet. 4/mmm(4/m2/m2/m) : P4/ncc
8.EB.10MetatorberniteCu(UO2)2(PO4)2 · 8H2OTet. 4/m : P4/n
8.EB.10MetazeuneriteCu(UO2)2(AsO4)2 · 8H2OTet. 4/m : P42/n
8.EB.10PrzhevalskitePb2(UO2)3(PO4)2(OH)4 · 3H2OTet.
8.EB.10'Pseudo-autunite'(H3O)4Ca2(UO2)2(PO4)4 · 5H2OOrth.
8.EB.15AbernathyiteK(UO2)(AsO4) · 3H2OTet. 4/mmm(4/m2/m2/m) : P4/ncc
8.EB.15Uramphite(NH4)2(UO2)2(PO4)2 · 6H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
8.EB.15Meta-ankoleiteK2(UO2)2(PO4)2 · 6H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
8.EB.15NatrouranospiniteNa2(UO2)2(AsO4)2 · 5H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
8.EB.15Trögerite(H3O)(UO2)(AsO4) · 3H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
8.EB.15Chernikovite(H3O)2(UO2)2(PO4)2 · 6H2OTet. 4/mmm(4/m2/m2/m) : P4/nmm
8.EB.15Uramarsite(NH4)(UO2)(AsO4) · 3H2OTet. 4/mmm(4/m2/m2/m) : P4/mmm
8.EB.20ChistyakovaiteAl(UO2)2(AsO4)2(F,OH) · 6.5H2OMon.
8.EB.20ThreadgolditeAl(UO2)2(PO4)2(OH) · 8H2OMon.
8.EB.25Uranospathite(Al,◻)(UO2)2(PO4)2F · 20(H2O,F)Orth. mm2 : Pnn2
8.EB.25ArsenuranospathiteAl(UO2)2(AsO4)2F · 20H2OOrth. mm2 : Pnn2
8.EB.30Vochtenite(Fe2+,Mg)Fe3+(UO2)4(PO4)4(OH) · 12-13H2OMon.
8.EB.35CoconinoiteFe3+2Al2(UO2)2(PO4)4(SO4)(OH)2 · 20H2OMon.
8.EB.40RanunculiteHAl(UO2)(PO4)(OH)3 · 4H2OMon. 2/m : B2/b
8.EB.45TrianguliteAl3(UO2)4(PO4)4(OH)5 · 5H2OTric.
8.EB.50FurongiteAl13(UO2)7(PO4)13(OH)14 · 58H2OTric. 1 : P1
8.EB.55ArsenosabugaliteH0.5Al0.5(UO2)2(AsO4)2 · 8H2OTric. 1 : P1
8.EB.55SabugaliteHAl(UO2)4(PO4)4 · 16H2OMon. 2/m : B2/m
8.EB.60Horákite(Bi7O7OH)[(UO2)4(PO4)2(AsO4)2(OH)2] · 3.5H2OMon. 2/m : B2/b

RadioactivityHide

Radioactivity:
Element % Content Activity (Bq/kg) Radiation Type
Uranium (U) 46.5650% 11,641,250 α, β, γ
Thorium (Th) 0.0000% 0 α, β, γ
Potassium (K) 0.0000% 0 β, γ

For comparison:

  • Banana: ~15 Bq per fruit
  • Granite: 1,000–3,000 Bq/kg
  • EU exemption limit: 10,000 Bq/kg

Note: Risk is shown relative to daily recommended maximum exposure to non-background radiation of 1000 µSv/year. Note that natural background radiation averages around 2400 µSv/year so in reality these risks are probably extremely overstated! With infrequent handling and safe storage natural radioactive minerals do not usually pose much risk.

Interactive Simulator:

Note: The mass selector refers to the mass of radioactive mineral present, not the full specimen, also be aware that the matrix may also be radioactive, possibly more radioactive than this mineral!

Activity: –

DistanceDose rateRisk
1 cm
10 cm
1 m

The external dose rate (D) from a radioactive mineral is estimated by summing the gamma radiation contributions from its Uranium, Thorium, and Potassium content, disregarding daughter-product which may have a significant effect in some cases (eg 'pitchblende'). This involves multiplying the activity (A, in Bq) of each element by its specific gamma ray constant (Γ), which accounts for its unique gamma emissions. The total unshielded dose at 1 cm is then scaled by the square of the distance (r, in cm) and multiplied by a shielding factor (μshield). This calculation provides a 'worst-case' or 'maximum risk' estimate because it assumes the sample is a point source and entirely neglects any self-shielding where radiation is absorbed within the mineral itself, meaning actual doses will typically be lower. The resulting dose rate (D) is expressed in microsieverts per hour (μSv/h).

D = ((AU × ΓU) + (ATh × ΓTh) + (AK × ΓK)) / r2 × μshield

Fluorescence of NováčekiteHide

Fluoresces dull green to bright lemon yellow in both LW and SW.

Other InformationHide

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 NováčekiteHide

References for NováčekiteHide

Localities for NováčekiteHide

Showing 28 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.
Hide all sections | Show all sections

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
 
  • Salzburg
    • Zell am See District
      • Rauris
Strasser (1989)
Strasser (1989)
Brazil
 
  • Bahia
    • Brumado
      • Serra das Éguas
King (n.d.)
Czech Republic
 
  • Karlovy Vary Region
    • Sokolov District
      • Horní Slavkov
70 (in German) +1 other reference
  • Ústí nad Labem Region
    • Chomutov District
      • Měděnec
Hyrsl et al. (2009)
France
 
  • Auvergne-Rhône-Alpes
    • Haute-Savoie
      • Bonneville
        • Vallorcine
Meisser (2012)
  • Occitanie
    • Hérault
      • Lodève
        • Le Puech
Bariand et al. (1993) +1 other reference
Germany
 
  • Baden-Württemberg
    • Freiburg Region
      • Ortenaukreis
        • Oberwolfach
Walenta (1980) +3 other references
        • Seelbach
          • Seelbach
            • Weiler
Walenta et al. (1961) +1 other reference
      • Rottweil
        • Schenkenzell
          • Wittichen
Ko Jansen collection +2 other references
Greece
 
  • Attica
    • East Attica
      • Lavreotiki
        • Plaka
          • Paliokamariza Mines (Paleokamariza Mines)
Rieck et al. (2018) +1 other reference
Italy
 
  • Piedmont
    • Cuneo Province
      • Bagnolo Piemonte
Marello et al. (2013)
Marello et al. (2013)
Mexico
 
  • Chihuahua
    • Aldama Municipality
      • Sierra Gomez range
Megaw (2023)
Morocco
 
  • Drâa-Tafilalet Region
    • Ouarzazate Province
      • Amerzgane Cercle
        • Ouisselsate Caïdat
ONA
Favreau et al. (2019)
    • Zagora Province
      • Agdz Cercle
        • Tansifte Caïdat
          • Tamdrost
Favreau et al. (2007)
Poland
 
  • Lower Silesian Voivodeship
    • Karkonosze County
      • Kowary
        • Podgórze
Syczewski et al. (2023)
Romania
 
  • Suceava County
Hîrtopanu P. et al. (2004)
Russia
 
  • Adygea (Republic of Adygea)
    • Maykopsky District
Pekov I.V. et al. (2010)
Slovakia
 
  • Košice Region
    • Gelnica District
      • Prakovce
Ondrejka et al. (2024)
Switzerland
 
  • Valais
    • Sierre
      • Anniviers
        • Saint-Luc
Ansermet (2012)
UK
 
  • Scotland
    • Dumfries and Galloway
Livingstone (1993)
USA
 
  • Alaska
    • Prince of Wales-Hyder Census Area
      • Ketchikan Mining District
        • Prince of Wales Island
          • Bokan Mountain
Dostal (2023)
  • New Mexico
    • Cibola County
      • Laguna subdistrict
Eric Quinter collection
  • Oregon
    • Lake County
      • Lakeview
R. E. Cohenour (1960)
  • Texas
    • Oldham County
Page et al. (1956) +3 other references
  • Utah
    • San Juan County
      • Red Canyon Mining District
Collected and analyzed by Joy Desor.
 
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