Zenith Minerals (ASX: ZNC) has received further positive analyses from a programme of follow-up metallurgical tests on REE samples from the company’s 100% owned Laramie REE project in Wyoming, USA.
- Testwork to date shows Laramie REE’s are dominantly contained in the mineral allanite; and
- 40 new analysis of individual allanite grains (by SEM/EDS) show that allanite contains total rare earth oxide (TREO) concentrations averaging 26%TREO whilst the high value REE component contains an encouraging average concentration of 6% neodymium and praseodymium oxide (Nd2O3+Pr2O3) or 23% of TREO
These new analyses follow on from previous positive first pass initial tests that showed that simple mineral separation techniques using either magnetic separation or gravity separation methods at coarse grain sizes will allow upgrading through concentration of the allanite (REE minerals) from the Laramie REE project.
Zenith reported that mineral separation by magnetic methods recovered 87% of the REE minerals into 27% of the mass at a crush size of -0.5mm, whilst mineral separation using gravity methods recovered 76% of the REE minerals into 22.2% of the mass at a crush size of -2mm.
The magnetic metallurgical tests completed to date were completed on laboratory/pilot scale testing equipment that has “off-the-shelf” industry standard commercial processing equivalents, hence the focus of follow-up work will be using the magnetic separation method.
Samples tested were first pass low grade (0.9% to 5.2% TREO) allanite concentrates from Phase 1 magnetic & gravity metallurgical testwork generated from the recent systematic chip sample traverses that returned results: 80m @ 0.40% TREO and 137m @ 0.37% TREO, indicating potential for large tonnages (ZNC ASX Release 6th Nov 2019).
The company told shareholders the very encouraging have supported Board approval to proceed with Stage 2 follow-up test work.
Stage 2 test work will now assess how easy it is to liberate the REE minerals from the REE concentrate generated by the Phase 1 magnetic separation. The follow-up test will involve finer grinding and subjecting the concentrate to both magnetic and flotation separation methods. This work has now commenced.