Suggest people look closely at the SEM images, consider that the higher Nb grades are in the weathered supergene layer, that " the
dominant niobium mineral is pyrochlore" only more than others, including very likely Nb in the Ti minerals that spike in grade over the same intervals, that fresh rock has much lower average grades than supergene, that Niobium market is small and WA1 will have to muscle in first, second and third for supply...
Images converted to same scale below. Black scale bar 200 micron. Weathered Pyrochlore and Baotite break up into extremely fine particles requiring extremely fine grinding to liberate and difficulty recovering with float. Good size fresk rock Pyrochlore low grade, deep, hard rock grinding etc. Also, still waiting on weathered supergene RE mineralogy met work aren't we??
Each to their own I suppose... GLTAH
(20min delay)