Mineral Liberation Analysis (MLA)
The SEM is equipped with sophisticated software that allows quantitative evaluation of the abundances, associations, sizes and shapes of minerals in automated, systematic fashion. The primary use of this tool in the IIC is for mine products such as ore concentrates and residues – particularly from the Voisey's Bay deposit in Labrador. The term mineral liberation analysis refers to an important characteristic of pre-processed ore, as well as the processed product; that is, to what degree are the important minerals liberated, or free of non-economic minerals? This characteristic is very important for making ore processing efficient, or to know if processing an ore is even economically viable. However, the characteristic belongs to a much broader subject of mineral associations, including all rock forming minerals, which will be included in our research at the IIC.
The MLA software was developed at the University of Queensland (Australia) Julius Kruttschnitt Mineral Research Centre (JKTech). The technique first relies on backscattered electron imaging (BEI), as a measure of average atomic number, for discriminating grain boundaries, and then offers a variety of x-ray options for classifying the grains as recognised minerals. Whereas the minerals' industry has long used MLA for epoxy-embedded grain mounts, our researchers will be expanding the scope of quantified mineral associations to include mineral assemblages within traditional polished rock thin sections.
As of the opening of the IIC research centre, this MLA is unique – it is only the second unit installed at a university with a mandate for research innovation and is the first in existence to use a new technology for high-resolution, ultra-high speed x-ray detection. Whereas JKTech had previously relied on 2 traditional Si(Li) detectors in tandem for speed, current benchmarks are implying the Xflash detector approaches a combination of 4 traditional detectors, and still provides better energy resolution.