Assessment of a spodumene ore by advanced analytical and mass spectrometry techniques to determine its amenability to processing for the extraction of lithium

A combination of analytical microscopy and mass spectrometry techniques have been used to detect and characterise different lithium minerals in a LCT-Complex spodumene-type pegmatite from Pilgangoora located in the Pilbara region of Western Australia. Information collated by these techniques can be used to predict processing amenability. Samples were categorised into three subsamples (Pil1, Pil2, Pil3) based on colour and texture having different lithologies. The mineralogy and liberation characteristics of samples were characterised using automated mineralogy techniques and the Li content and elemental distribution within minerals defined using instrumentation with secondary mass spectrometry capabilities. The majority of lithium is associated with spodumene particles with minor amounts of lithium bearing micas and beryl in the Pil1 sample, whereas in Pil2 and Pil3 spodumene is largely the lithium source. In the Pil1 sample a proportion of spodumene particles have undergone alteration with spodumene being replaced by micaceous minerals of muscovite, lepidolite and trilithionite, as well as calcite. In Pil2 and Pil3 samples the spodumene particles are generally free of mineral impurities except minor intergrowths of quartz, feldspar and spodumene are evident in the coarser fractions. Based on mineralogical observations in the current study, the majority of the main gangue minerals quartz, K feldspar and albite can be rejected at a coarse grind size of −4 mm, to recover 90% of the spodumene with Li upgrade from 0.99–1.5 wt% Li to 3.0–3.5 wt% (6.5–7.5 wt% Li 2 O). The iron content (81–1475 ppm) in the spodumene is low and therefore make these spodumene concentrates suitable for use in ceramic and glass applications. Recovery of spodumene in the coarse fractions could be improved by further particle size reduction to liberate spodumene from micas and feldspars in the middling class, which account for between 15 and 49% of the sample. However, the requirement to remove mineral impurities in the spodumene in downstream processing will be dependent on the method of processing as the presence of Li bearing micas, calcite and feldspar can be beneficial or detrimental to lithium recovery. The high content of Rb (1 wt%) and the abundance of free grains makes K feldspar a source of rubidium, particularly in the Pil3 sample which has K feldspar in high abundance (21 wt%) and can potentially be recovered by reverse flotation technique. The low concentrations of the Ta, Nb and Sn minerals identified in samples were found to be fairly well liberated and could be recovered by conventional gravity separation techniques

Management and curation of rock samples in a geochronology lab: Linking physical samples to data,John de Lateter Centre Digital Mineral Library Project

Talk presented to eResearch Australasia 2016, Wednesday 12 October 2016 entitled "Management and curation of rock samples in a Geochronology Lab: Linking physical samples to data, John de Laeter (JdLC) Digital Mineral Library Project". The talk reports on research projects at the JdLC, Curtin University, Western Australia to develop a Laboratory Information Management System (LIMS) to capture, store, manage and share geochemical analyses related to geochronology using two of the instruments housed at the (TIMA - a type of SEM-EDA used to determine the mineral composition of rock samples and a SHRIMP - a secondary ion mass spectrometer used to measure uranium and lead isotope concentrations in minerals)

Applications of advanced analytical and mass spectrometry techniques to the characterisation of micaceous lithium-bearing ores

With the impetus for less reliance on fossil fuels and an increasing demand for environmentally friendly energy materials, lithium is emerging as an important material of the future. The ability to extract lithium from ores economically is essential. However, a comprehensive understanding of the deportment of lithium and associated minerals in some ore bodies is limited. A combination of analytical microscopy and mass spectrometry techniques has been used to allow detection and characterisation of different lithium minerals in three micaceous Li-bearing ores. To quantify the different Li-bearing ore minerals, the chemistry and structural characteristics of a suite of lithium mineral specimens were first examined. The micas can be classified and grouped based on their compositions (Al/Si ratio; F, Na content) and used to distinguish different micas with different lithium grades. Micas exist as different polymorphs that are generally related to composition and also geological environment. The mineralogy, mineral associations and liberation characteristics of both ore-bearing and gangue minerals were characterised using automated mineralogy techniques and the Li content and elemental distribution within minerals defined using instrumentation with secondary mass spectrometry capabilities. The majority of lithium in the ore samples (1.2–1.5% Li) examined is associated with lepidolite or zinnwaldite particle compositions which are made up of Li muscovite, trilithionite and polylithionite grains. The morphology of the Li-bearing micas varies in different deposits. The gangue materials are predominately quartz and albite and make up ≤20 w% of the sample. Only minor amounts (∼1%) of other Li-bearing minerals (e.g. spodumene, elbaite, beryl) were observed in these samples. The Ta grade associated with minerals rynersonite and columbite-tantalite in some samples may be economic. The majority of the Li mica particles were liberated from the major gangue minerals under the conditions used to treat and screen samples to pass a 4 mm sieve. Further grinding will be required to breakup and expose fine grains of Li muscovite, polylithionite, and trilithionite, for further treatment to extract Li. The processes used to breakdown the micas to extract Li will also require stabilising and removal of F, Fe, Al, Mn and monovalent ions K and Na from process streams. The high concentration of Rb (0.9–3.6 wt%) and Cs (0.1–0.8 wt%) make mica a favourable resource for these elements and they can ultimately be recovered along with Li

Mineralogy and Petrology of the Murrili Meteorite

No abstract available