What is MLA?
MLA - What is it?
MLA - or Mineral Liberation Analyser - is a quantitative mineralogy system that integrates Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectrometry (EDS) analysis technologies. Samples are presented to the SEM in a range of forms from polished blocks, to polished thin sections and polished sections of solid and particulate materials.
Under the SEM, different minerals or phases are discriminated from one another on the basis of combined differences in backscatter electron (BSE) signal intensity captured by image analysis and the acqusition of characteristic X-Ray spectra (by EDS) of component grains and particles. The X-ray spectra are stored during measurement and later compared with a library of standard mineral spectra to identify and quantify component minerals.
Three key benefits of the MLA650F system are that: (1) Automated searches for trace or rare minerals are based on TV-rate image scanning (and are hence rapid), (2) X-Ray resolution is keyed directly to the integrated EDS X-ray system and (3) The use of a Field Emission Gun (FEG) electron source, rather than a traditional W-filament electron source by conventional SEM. The result is superior spatial and X-ray resolution with the capability of locating and positively identifying even sub-micron sized minerals, with improved confidence in data and more cost-effective instrument utilization and throughput.
Different measurement modes are available, depending on the client’s needs and/or the problem at hand. Options range from simple point-counting to advanced X-ray and particle mapping, whereby orders of magnitudes of measurements (from thousands to millions) of point- and/or particle-counts are routinely performed in automated, unattended operation. Relative to historic, manual point counting methods, robust statistics are achievable which provide an accurate mineralogical account of - and hence link to explaining and interpreting - geochemical and specific element variations and deportment.
|