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Customized Spectral Libraries for Effective Mineral Exploration: Mining National Mineral Collections

Published online by Cambridge University Press:  01 January 2024

Jeanne B. Percival ,
Sean A. Bosman ,
Eric G. Potter ,
Jan M. Peter ,
Alexandra B. Laudadio ,
Ashley C. Abraham ,
Daniel A. Shiley  and
Chris Sherry
Jeanne B. Percival*
Affiliation:
Geological Survey of Canada, Ottawa, Ontario, Canada K1A 0E8
Sean A. Bosman
Affiliation:
Saskatchewan Geological Survey, Regina, Saskatchewan, Canada S4P 3Z8
Eric G. Potter
Affiliation:
Geological Survey of Canada, Ottawa, Ontario, Canada K1A 0E8
Jan M. Peter
Affiliation:
Geological Survey of Canada, Ottawa, Ontario, Canada K1A 0E8
Alexandra B. Laudadio
Affiliation:
Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada K1S 5B6
Ashley C. Abraham
Affiliation:
Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada K1S 5B6
Daniel A. Shiley
Affiliation:
ASD Inc.-Malvern Panalytical, Longmont, Colorado, USA 80503
Chris Sherry
Affiliation:
Consultant Geologist, Morrison, Colorado, USA 80465
*
*E-mail address of corresponding author: jeanne.percival@canada.ca
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Abstract

Infrared (Visible-Near Infrared-Shortwave Infrared (VNIR-SWIR)) spectroscopy is a cost-effective technique for mineral identification in the field. Modern hand-held spectrometers are equipped with on-board spectral libraries that enable rapid, qualitative analysis of most minerals and facilitate recognition of key alteration minerals for exploration. Spectral libraries can be general or customized for specific mineral deposit environments. To this end, careful collection of spectra in a controlled environment on pure specimens of key minerals was completed using the National Mineral Reference Collection (NMC) of the Geological Survey of Canada. The spectra collected from specimens in the ‘Kodama Clay Collection’ were processed using spectral plotting software and each new example was validated before being added to a group of spectra considered for incorporation into the on-board library of the handheld ASD-TerraSpec Halo near-infrared (NIR) mineral identification instrument. Spectra from an additional suite of mineral samples of the NMC containing REE, U, Th, and/or Nb are being prepared for a new, publicly available spectral library. These minerals commonly occur in carbonatite or alkali intrusive deposits, and as such will assist in the exploration for critical metals.

Keywords

ASD-TerraSpecClay MineralsInfrared SpectroscopyNational Mineral Reference CollectionNear InfraredOptical Reflectance SpectroscopyREE-bearing MineralsShortwave Infrared
Type
Article
Information
Clays and Clay Minerals , Volume 66 , Issue 3 , June 2018 , pp. 297 - 314
Copyright
Copyright © Clay Minerals Society 2018

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