Re: Radiation on Southern India Coast

[DWMCCARN@aol.com]

In a message dated 5/11/99 4:20:55 PM E. Europe Daylight Time, 
frantaj@aecl.ca writes:

<< >         AZEEKKAL, India (AP) _ More than 100,000 poor villagers are
 >  living in a small coastal region of southern India that is
 >  unusually rich in naturally occurring radioactive materials. >>

     Monazite beach placers are well known and common in southern India, and 
form detridal stream and beach deposits because the mineral is moderately 
resistant to weathering (H=5) and has a relatively high density (D=5.0-5.3).  
 At one time, they were considered a potential resource for Th reactors.  
Monazite contains typically 4-12% ThO2, and a similar mineral, cheralite, may 
contain as much as 30% ThO2.  Beach placers have been worked for their cerium 
content.  Monazite and Huttonite are end-members of SiO4 replacement for PO4.

Monazite 	(Ce,La,Th) (PO4)
Cheralite	(Th,Ca,Ce,U,Pb) (PO4,SiO4)
Huttonite	ThSiO4

Best regards,

Dan W. McCarn
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