On the accuracy of the mineral analysis performed by electron microprobe

• Main Author: J. Siivola
• Format: Article
• Language: English
• Published: Geological Society of Finland 1970-12-01
• Series: Bulletin of the Geological Society of Finland
• Online Access: http://www.geologinenseura.fi/bulletin/Volume42/sgs_bt_042_pages_037_051.pdf

In the first part of the paper theoretical principles of the electron microprobe analysis are reviewed. Stress is laid on the absorption correction which is discussed in greater detail. The second part deals with a series of measurements demonstrating the magnitude of the absorption correction and the accuracy of the final results. The analyses were performed using both oxide and silicate standards. The results were calculated applying Philibert's primary absorption correction term. Comparing the results with those of wet chcmical analysis the following limits for the accuracy (in percent) of microprobe analysis are obtained: SiO2 ±0.9, Al2O3 ±0.4, Fe2O3 ±1.5, MgO ±0.5 and CaO ±0.7. Furthermore, the measurements indicate that when analysing small concentrations in silicate minerals using a silicate standard, there is a linear relationship between the recorded X-ray line intensity and the concentration to be analysed.