Electron microprobe compositional mapping and dating was carried out on abundant monazite and thorite in relatively fresh samples from the Lucky Horseshoe Mine. The low Th (0.2-0.6 wt%) and U (<200ppm) of the bulk monazite makes precise age quantification difficult (Pb < 300ppm) by EMPA, ...
Molybdenite from the dump of the Copper Queen mine (qtz-cp-bn-mo) was collected for Re-Os geochronology. The molybdenite, which contained a remarkably low Re concentration (0.2716 ppm), provided an age of 1055+ or -4 Ma. Monazite and thorite from two fresh samples of specularite-biotite-...