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UM1985-27-SiO:FeU

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Formula:
U4FeSi3O15
possible formula
One of four U-Fe- silicates ("unidentified phase 1"), beside 'UM1985-28-SiO:FeU', 'UM1985-29-SiO:FeU', and 'UM1985-30-SiO:FeU', from the same locality. All four represent the only known natural purely U-Fe silicates. 'UM1984-39-SiO:U' is also mentioned from the same metallogenic zone in Bulgaria.

All the unnamed species occur as tiny, up to 0.1 mm, individuals, that are isometric to irregular in shape. They were found along cracks within layered aggregates (up to 1 mm thick) composed mainly of uraninite, pitchblende, "hydronasturan", and minor chalcopyrite, galena, hematite, pyrite, and sphalerite.

Compare also 'UM1983-25-SiO:U' and similar species, most likely also from Bulgaria.

It is not specified, if this species also occurs in Lenz im Kaltenegg, Styria, Austria.


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Unique IdentifiersHide

Mindat ID:
47848
Long-form identifier:
mindat:1:1:47848:3

Similar NamesHide

UM1985-28-SiO:FeUU5Fe2Si5O22
UM1985-29-SiO:FeUU4Fe5Si4O21
UM1985-30-SiO:FeUUFe6Si2O12 · 5H2O
UM2006-22-SiO:VVSiO3(OH) (?)

Physical Properties of UM1985-27-SiO:FeUHide

Hardness:
VHN100=320 - 405 - Vickers

Chemistry of UM1985-27-SiO:FeUHide

Mindat Formula:
U4FeSi3O15

possible formula
Element Weights:
Element% weight
U71.469 %
O18.015 %
Si6.325 %
Fe4.192 %

Calculated from ideal end-member formula.
Elements listed:
Fe, 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 UM1985-27-SiO:FeUHide

References for UM1985-27-SiO:FeUHide

Localities for UM1985-27-SiO:FeUHide

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.

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
 
  • Styria
    • Weiz District
      • Rettenegg
        • Prinzkogel (Prinzenkogel)
          • Prinzkogel mines
            • Southern District
              • Kaltenegg
Simova (1984)
Bulgaria
 
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