Drill core photo and QEMSCAN image from the top of drill hole HK20-004 (a proxy for the top of Hole 13 drilled from the same collar) showing altered magnetite needles with reaction rims of pyrite–pyrrhotite–iron carbonate and bastnaesite (LREE)–pyrochlore (Na,Ca)2Nb2O6(OH,F) in a matrix of apatite with calcite inclusions containing monazite ((Ce,La,Nd,Th)PO4), quartz and potassium feldspar. The magnetite-quartz-potassium feldspar assemblage is a high temperature potassic alteration facies.
Drill core photo and QEMSCAN image from the top of drill hole HK20-004 (a proxy for the top of Hole 13 drilled from the same collar) showing altered magnetite needles with reaction rims of pyrite–pyrrhotite–iron carbonate and bastnaesite (LREE)–pyrochlore (Na,Ca)2Nb2O6(OH,F) in a matrix of apatite with calcite inclusions containing monazite ((Ce,La,Nd,Th)PO4), quartz and potassium feldspar. The magnetite-quartz-potassium feldspar assemblage is a high temperature potassic alteration facies.