Reference materials
Introduction:
These pages provide information on the chemical composition of
reference materials available for geochemical analysis. For each
reference material, up to three sources of information are listed:
* Certificate represents reference
values published
by the issuing body, often in the form of a certificate of analysis.
These data represent the 'official' composition of the respective
samples.
* IAEA compilation represents data
published by the
International Atomic Energy Agency, Vienna and is compiled from
certificates of analysis, information sheets, and other reports
provided by the reference material producers. More detailed information
on compilation and terminology can be found here .
* Gladney's compilation is a compilation
of data
mainly derived from a statistical analysis (incorporating outlier
rejection) of reference material values published in the scientific
literature.
In accordance with current recommendations from ISO (The International
Organisation for Standardisation), issuing bodies should take
responsibility for reference values. Where there are differences in
values between these three compilations, the issuing body value should
take precidence.
Where available, each value is accommpanied by an uncertainty, being
the interval within which the true value is expected to lie, within a
stated degree of confidence. Different conventions are used for
specifying confidence limits, so users are advised to examine carefully
source data to identify the units used for this quantity. In any case,
use and interpretation of any reference data should take account of the
corresponding uncertainty limits.
A more extensive discussion of these principles can be found in:
Kane,J.S. and Potts P.J. (1997). ISO guides for reference material
certification and use: Application to geochemical reference materials.
Geostandards Newsletter: The Journal of Geostandards and Geoanalysis,
21, 51-58.
The IAG is very grateful to E. Gladney (Los Alamos National
Laboratory), for making his compilation available.
Other source of results for Reference materials:
GeoReM
IAEA
Last
update: 2008-1-21 Webmaster
: pbedard «at» uqac «dot» ca