Open AccessTrace-element imaging at macroscopic scale in a Belgian sphalerite-galena ore using Laser-Induced Breakdown Spectroscopy (LIBS)
Author(s) -
JeanMarc Baele,
Hassan Bouzahzah,
Séverine Papier,
Sophie Decrée,
Sophie Verheyden,
Christian Burlet,
Eric Pirard,
Guy Franceschi,
Léon Dejonghe
Publication year - 2021
Publication title -
geologica belgica (printed)/geologica belgica (online)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.227
H-Index - 21
eISSN - 2034-1954
pISSN - 1374-8505
DOI - 10.20341/gb.2021.003
Subject(s) - sphalerite , laser induced breakdown spectroscopy , galena , trace element , spectroscopy , analytical chemistry (journal) , mineralogy , elemental analysis , materials science , geology , metallurgy , chemistry , environmental chemistry , inorganic chemistry , pyrite , physics , quantum mechanics
Laser-Induced Breakdown Spectroscopy (LIBS) is a fast in-situ analytical technique based on spectroscopic analysis of atomic emission in laser-induced plasmas. Geochemical mapping at macroscopic scale using LIBS was applied to a decimetric Zn-Pb ore sample from east Belgium, which consists of alternating sphalerite and galena bands. A range of elements was detected with no or minimal spectral correction, including elements of interest for beneficiation such as Ge, Ag and Ga (although the detection of gallium could not be confirmed), and remediation, especially As and Tl. The comparison between LIBS and Energy Dispersive Spectroscopy (EDS) analyses showed that LIBS intensities reliably relate to elemental concentration although differences in spot size and detection limits exist between both techniques. The elemental images of minor and trace elements (Fe, Cu, Ag, Cd, Sb, As, Tl, Ge, Ni and Ba) obtained with LIBS revealed with great detail the compositional heterogeneity of the ore, including growth zones that were not visible on the specimen. In addition, each mineral generation has a distinct trace-element composition, reflecting a geochemical sequence whose potential metallogenic significance at the district scale should be addressed in further work. Although qualitative and preliminary, the obtained LIBS dataset already produced a wealth of information that allowed to initiate discussion on some genetical and crystallochemical aspects. Above all, LIBS appears as a powerful tool for screening geochemically large samples for the selection of zones of particular interest for further analysis.