LIBS Info: Element Analysis

Title Authors Material Detector Spectrometer Software
Analysis of gold in rock samples using laser-induced breakdown spectroscopy: Matrix and heterogeneity effects Blandine Nguegang Kamwa, Maryline Castello, Konstantinos Fytas, Paul Bouchard, Alain Blouin, M. Sabsabi, Francois Vidal, Marc Constantin, Marcel Laflamme, Kheireddine Rifai Geological Andor ICCD Czerny-Turner (Unspecified)
Laser: Nd:YAG
Gate Delay: 2.000us
Gate Width: 10.000us
LIBS analysis of rock powders and drill cores [the key resources of any geological analysis] for Gold (Au) content. For calibration curves, 44 pressed powder samples are used in the range 0-1000ppm. The authors use a PCA based classification scheme that enabled different normalisation schemes to be applied to different mineralogies [Si vs Fe rich]. This calibration curve was then tested on drill core samples.
Element Detection Limit (ppm) Wavelength (nm) Other Wavelengths (nm) Calibration Method Calibration Range (ppm) Notes
Au 1.5000 (Calibration Curve Slope) 267.5900 N/A Univariate 0.0000-932.0000 PCA used to determine if sample high in Si or Fe. This is the LOD for high Fe samples (due to interference from Fe lines neighbouring Au line). Key to the determination was analysis on a blank (no Au) sample.
Au 0.7500 (Calibration Curve Slope) 267.5900 N/A Univariate 0.2800-891.0000 From Pressed powder samples with high Si, low Fe concentrations.

Element RMSE (ppm) Wavelength (nm) Calibration Method Notes
Au 3.5372 ppm 267.5900 Univariate Calibration . . . . A univariate calibration, with initial PCA step (to separate Si rich from Fe rich samples). . . .