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UM1986-64-SiO:NbREETi

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Formula:
~(Nd,Ce,REE)6Ti24Nb4Si12O91
(semi)metallic element ratios ca. (Nd,Ce,REE)3Ti12Nb2Si6
Colour:
brown to brownish-yellow
Lustre:
Vitreous
Hardness:
5 - 6
Specific Gravity:
4.71 - 4.76
Unique combination of elements. The phase is interesting in having Ti and Nb located on separate structural positions (however, as suggested by the ideal formula only), which is not very common among the known minerals.

Forms grains, tabular, in radiating aggregates. Coexists with barite and Na-rich pyroxene.


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Unique IdentifiersHide

Mindat ID:
51522
Long-form identifier:
mindat:1:1:51522:5

Physical Properties of UM1986-64-SiO:NbREETiHide

Lustre:
Vitreous
Colour:
Brown to brownish-yellow
Comment:
Transmitted light: light reddish-brown
Streak:
Dark brown
Hardness:
5 - 6 on Mohs scale
Density:
4.71 - 4.76 g/cm3 (Measured)    

Chemistry of UM1986-64-SiO:NbREETiHide

Mindat Formula:
~(Nd,Ce,REE)6Ti24Nb4Si12O91

(semi)metallic element ratios ca. (Nd,Ce,REE)3Ti12Nb2Si6
Element Weights:
Element% weight
O34.841 %
Ti27.491 %
Nd20.710 %
Nb8.893 %
Si8.065 %

Calculated from ideal end-member formula.
Elements listed:
Ce, Nb, Nd, O, Si, Ti - search for minerals with similar chemistry

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 UM1986-64-SiO:NbREETiHide

References for UM1986-64-SiO:NbREETiHide

Localities for UM1986-64-SiO:NbREETiHide

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.
China
 
  • Inner Mongolia
    • Baotou City (Baotou Prefecture)
      • Bayan Obo mining district
        • Bayan Obo
Peishan Zhang (1986) +1 other reference
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