These specimens show yellowish nodules included in a feldspar matrix. First SEM-EDS analysis have yielded a phosphate of Th and Ca, with minor Pb. XRD has shown patterns of "bravantite", the old name for cheralite and brockite. The chemical base formula for these species are: grayite (Th,Pb,Ca)(PO4)·H2O; cheralite CaTh(PO4)2; brockite (Ca,Th,Ce)(PO4)·H2O. REE has not been found in EDS.
We could say that this yellow nodules belongs from altered monazite, formed by mixed species cheralite-grayite, with minor brockite. Accompanied in matrix by meta-autunite. We will send the full report.

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