Re: Natural Thorium

[DWMCCARN@aol.com]

Dear Elizabeth:

About 15% (or more) of the uranium-bearing minerals are also reported to 
contain thorium.  Here is a short list:

Aeschynite	(Ce,Ca,Fe++,Th) (Ti,Nb)2 (O,OH)6
Bilibinite	3(Ca,Pb)O (U,Th)O2 7UO3 10SiO2 19H2O
Brannerite	(U,Ca,Fe,Th,Y)3 Ti5O16
Calciomarksite	(Ca,Y,Ce,U,Th)3 (Nb,Ta,Fe,Ti,Sn)5 O15
Cerphosphorhuttonite	(Th,Ce) (Si,P)O4 1.5H2O
Cheralite	(Th,Ca,Ce,U,Pb) (PO4,SiO4)
Chevkinite	(Ce,Y,Ca,U,Th)2 (Ti,Fe,Mg)2 (Si,Al)2 O11
Clarkeite	(Na,Ca,Pb,Th,H2O)2 U2 (O,H2O)7
Davidite	(Fe,Ce,La,Y,U,Ca,Zr,Th) (Ti,Fe,V,Cr)3 (O,OH)7
Ekanite	(Th,U) (Ca,Fe,Pb)2 Si8O20
Euxenite	(Y,Ca,Ce,U,Th) (Nb,Ta,Ti)2 O6
Formanite	(Y,U,Th,Ca) (Ta,Nb,Ti) O4
Huttonite	ThSiO4
Khlopinite	(Y,U+4,Th)3 (Nb,Ta,Ti,Fe)7 O20 (?)
Kivuite	(Th,Ca,Pb) H2 (UO2)4 (PO4)2 (OH)8 7H2O
Microlite	(Na,Ca)2 Ta2O6 (O,OH,F) or 
(Na,Ca,Fe++,U+4,Sb+++,Pb,Th,Zr,Ce,Y)2 (Nb,Ta,Ti,Sn,Fe+++)2 O6(O,OH,F)
Monazite	(Ce,La,Th) (PO4)
Pilbarite	PbO ThO2 UO3 2SiO2 4H2O
Pisekite	Th,Sn,RE,U,Nb,Ta,Ti
Polycrase	(Y,Ca,Ce,U,Th) (Ti,Nb,Ta)2O6
Priorite	(Y,Er,Ca,Fe++,Th) (Ti,Nb)2O6
Samarskite	(Y,Ce,U,Ca,Fe,Pb,Th) (Nb,Te,Ti,Sn)2 O6
Sinicite	(Ce,Y,U,Th) (Ti,Nb mainly)2 (O,OH)7
Steenstrupine	(Ca,La,Th,Na)2 (Mn,Fe) (SiO3)2 (OH)2 2H2O
Thorianite	ThO2
Thorite	(Th,U,Ce,Fe,etc.) (SiO4)
Thorogummite	(Th,U,Ce,etc.) (SiO4)1-x (OH)4x
Thorutite	(Th,Ca,U) Ti2 (O,OH)6
Yttrialite	(Y,Th)2 Si2O7
Yttrocrasite	(Y,Th,U,Ca)2 Ti4O11 (?)
Zirkelite	(Ca,Fe,Th,U)2 (Ti,Nb,Zr)2 O7 (?)

D. McCarn
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