Geology & Minerals
Spectroscopy of Minerals
It is known that minerals develop spectral signatures in the various spectral regions. For the various spectral regions there are optical instruments that can record the visible, infrared and other characteristic spectra of minerals. Based on the spectral information, the different materials can be identified from previously recorded spectral libraries. Hyperspectral Imaging of drill core samples have been measured with different spectroscopic methods but the conventional methods only measure an average of an area or a small section of the available surface of the sample. Hyperspectral imaging is capable of exploring the spectral signatures of each point of samples. The spatial distribution of the specific minerals obtained using hyperspectral imaging describes not only the composition and location of the minerals but the genesis of the geologic samples can be inferred from the images.
Most minerals can be sorted with optical methods, and those that differ in color or texture and can be sorted using the VNIR spectral range. Various source sites may have minerals that are similar in color but have different chemical compositions. The distinct spectral characteristics of these inorganic materials can be scanned by a hyperspectral camera placed above a moving belt carrying the rocks. Real time high throughput sensing allows the individual rocks to be characterized and sorted further downstream from the camera.
Large savings are possible when enriching the product stream of the desired mineral by reducing the downstream chemical extraction and other unit processing steps. The chemicals used in extraction are usually the most damaging to the environment, thus the reduction or elimination of chemical extraction is a major advantage to the mining industry.