thumbnail

Comparison of rapid methods for chemical analysis of milligram samples of ultrafine clays

Clays and Clay Minerals

By:
, , , and
https://doi.org/10.1346/CCMN.1983.0310605

Links

Abstract

Two rapid methods for the decomposition and chemical analysis of clays were adapted for use with 20–40-mg size samples, typical amounts of ultrafine products (≤0.5-µm diameter) obtained by modern separation methods for clay minerals. The results of these methods were compared with those of “classical” rock analyses. The two methods consisted of mixed lithium metaborate fusion and heated decomposition with HF in a closed vessel. The latter technique was modified to include subsequent evaporation with concentrated H2SO4 and re-solution in HCl, which reduced the interference of the fluoride ion in the determination of Al, Fe, Ca, Mg, Na, and K. Results from the two methods agree sufficiently well with those of the “classical” techniques to minimize error in the calculation of clay mineral structural formulae. Representative maximum variations, in atoms per unit formula of the smectite type based on 22 negative charges, are 0.09 for Si, 0.03 for Al, 0.015 for Fe, 0.07 for Mg, 0.03 for Na, and 0.01 for K.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Comparison of rapid methods for chemical analysis of milligram samples of ultrafine clays
Series title:
Clays and Clay Minerals
DOI:
10.1346/CCMN.1983.0310605
Volume:
31
Issue:
6
Year Published:
1983
Language:
English
Publisher:
The Clay Minerals Society
Description:
7 p.
First page:
440
Last page:
446