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UM1981-25-SiO:CaU

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Formula:
~(Ca,Mg,K,Ba)U7Si4O21
Hardness:
5
One of four Ca-U4+ silicate species from Žirovsky Vrh deposit, Slovenia (and likely also from Forstau, Salzburg, Austria). Corresponds to "Group 2" microprobe analyses. The species occur as irregular to equant grains, black to gray to lighter gray in colour. Associated with coffinite. Compare UM1981-24-SiO:CaU, UM1981-26-SiO:CaU, UM1981-28-SiO:CaU and 'UM1982-17-SiO:CaTiU'.

Compare arapovite - the only approved Ca- and U4+-bearing silicate mineral.


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Unique IdentifiersHide

Mindat ID:
47579
Long-form identifier:
mindat:1:1:47579:6

Similar NamesHide

UM1956-02-SiO:CaHUCaUSiO6 · H2O
UM1960-07-SiO:CaHUCa-U-Si-O-H
UM1977-14-SiO:CaHCa2SiO4 · H2O
UM1981-24-SiO:CaU~(Ca,K,Ba)U8Si2O21
UM1981-26-SiO:CaU~(Ca,K,Mg)U3Si11O29 (?)
UM1981-28-SiO:CaU~(Ca,K,Ba)U5Si11O33
UM1997-50-SiO:CaHUValid as an unnamed mineralCa2(UO2)2(Si2O5)3 · 10H2O
UM1999-34-SiO:CaA synonym of Breyite
UM1999-35-SiO:CaValid as an unnamed mineralCaSi2O5
UM2001-23-SiO:CaHUValid as an unnamed mineralCa(UO2)2(SiO3OH)2 · 5H2O
UM2005-31-SiO:CuHValid as an unnamed mineralCu11(SiO4)(OH)18 · 9H2O (?)

Physical Properties of UM1981-25-SiO:CaUHide

Hardness:
5 on Mohs scale

Chemistry of UM1981-25-SiO:CaUHide

Mindat Formula:
~(Ca,Mg,K,Ba)U7Si4O21
Element Weights:
Element% weight
U77.332 %
O15.594 %
Si5.214 %
Ca1.860 %

Calculated from ideal end-member formula.
U
O
Si
Ca
Elements listed:
Ba, Ca, K, Mg, O, Si, U - search for minerals with similar chemistry

RadioactivityHide

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 UM1981-25-SiO:CaUHide

References for UM1981-25-SiO:CaUHide

Localities for UM1981-25-SiO:CaUHide

Showing 2 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
 
  • Salzburg
    • St. Johann im Pongau District
      • Forstau
Simova (1981) +1 other reference
Slovenia
 
  • Gorenja Vas–Poljane
Simova (1981) +1 other reference
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