Hostname: page-component-7b7567c8c-wxvwp Total loading time: 0 Render date: 2026-11-15T17:41:50.041Z Has data issue: false hasContentIssue false

A precise and accurate method for the quantitative determination of carbonate minerals by X-Ray diffraction using a spiking technique

Published online by Cambridge University Press:  05 July 2018

H. A. Gunatilaka
Affiliation:
Sedimentology Research Laboratory, University of Reading, Reading, RG6 2AB, England
Roger Till
Affiliation:
Sedimentology Research Laboratory, University of Reading, Reading, RG6 2AB, England

Summary

A precise and accurate X-ray diffraction method has been developed whereby the weight percentages of aragonite and low- and high-magnesium calcite are determined from the integrated peak areas of spiked and unspiked samples. The spike mixture was prepared from organisms extracted from the samples to be analysed. Use of a spiking method also avoided the preparation of working curves from artificial mixtures of carbonate minerals, which may not have the same diffraction behaviour as the unknowns. A test of the precision of the method indicates the following coefficients of variation: aragonite, 1·4 %; low-magnesium calcite, 1·5 %; high-magnesium calcite, 7·8 %. A test of the accuracy of the method indicates no significant bias in any of the carbonate results, except in samples where high-magnesium calcite values are below 10 %. Quartz may also be determined by this method (coefficient of variation 23·9 %; positive bias in values greater than 10 %).

Information

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1971

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable