Thallium mass fraction and stable isotope ratios of sixteen geological reference materials
File(s)
Accepted version
Supporting information
Author(s)
Brett, Alex
Prytulak, J
Hammond, Samantha J
Rehkamper, M
Type
Journal Article
Abstract
Thallium stable isotope ratio and mass fraction measurements were performed on sixteen
geological reference materials spanning three orders of magnitude in thallium mass fraction,
including both whole-rock and partially-separated mineral powders. For stable isotope ratio
measurements, a minimum of three independent digestions of each reference material were
obtained. High-precision trace element measurements (including Tl) were also performed for the
majority of these RMs. The range of Tl mass fractions represented is 10 ng g
-1
to 16
μ
g g
-1
, and Tl
stable isotope ratios (reported for historical reasons as
ε
205
Tl relative to NIST SRM 997) span the
range -4 to +2. With the exception
–
attributed to between-bottle heterogeneity
–
of G-2, the
majority of data are in good agreement with published or certified values, where available. The
precision of mean of independent measurement results between independent dissolutions suggests
that, for the majority of materials analysed, a minimum digested mass of 100 mg is recommended to
mitigate the impact of small-scale powder heterogeneity. Of the sixteen materials analysed, we
therefore recommend for use as Tl reference materials the USGS materials BCR-2, COQ-1, GSP-2,
and STM-1; CRPG materials AL-I, AN-G, FK-N, ISH-G, MDO-G, Mica-Fe, Mica-Mg, and UB-N;
NIST SRM 607; and OREAS14P.
geological reference materials spanning three orders of magnitude in thallium mass fraction,
including both whole-rock and partially-separated mineral powders. For stable isotope ratio
measurements, a minimum of three independent digestions of each reference material were
obtained. High-precision trace element measurements (including Tl) were also performed for the
majority of these RMs. The range of Tl mass fractions represented is 10 ng g
-1
to 16
μ
g g
-1
, and Tl
stable isotope ratios (reported for historical reasons as
ε
205
Tl relative to NIST SRM 997) span the
range -4 to +2. With the exception
–
attributed to between-bottle heterogeneity
–
of G-2, the
majority of data are in good agreement with published or certified values, where available. The
precision of mean of independent measurement results between independent dissolutions suggests
that, for the majority of materials analysed, a minimum digested mass of 100 mg is recommended to
mitigate the impact of small-scale powder heterogeneity. Of the sixteen materials analysed, we
therefore recommend for use as Tl reference materials the USGS materials BCR-2, COQ-1, GSP-2,
and STM-1; CRPG materials AL-I, AN-G, FK-N, ISH-G, MDO-G, Mica-Fe, Mica-Mg, and UB-N;
NIST SRM 607; and OREAS14P.
Date Issued
2018-09-01
Date Acceptance
2018-04-16
Citation
Geostandards and Geoanalytical Research, 2018, 42 (3), pp.339-360
ISSN
1639-4488
Publisher
Wiley
Start Page
339
End Page
360
Journal / Book Title
Geostandards and Geoanalytical Research
Volume
42
Issue
3
Copyright Statement
© 2018 The Authors. Geostandards and Geoanalytical Research © 2018 International Association of Geoanalysts. This is the pre-peer reviewed version of the following article, which has been published in final form at https://onlinelibrary.wiley.com/doi/full/10.1111/ggr.12215
Subjects
Science & Technology
Physical Sciences
Geochemistry & Geophysics
thallium
stable isotopes
reference materials
powder heterogeneity
sample mass
UPPER CONTINENTAL-CRUST
MC-ICP-MS
DILUTION-INTERNAL STANDARDIZATION
GEOCHEMICAL REFERENCE SAMPLES
HIGH-PRESSURE DIGESTION
FLUID-ROCK INTERACTION
MEXICAN VOLCANIC BELT
EFFECTIVE IONIC-RADII
NUCLEAR-FIELD SHIFT
EARLY SOLAR-SYSTEM
0402 Geochemistry
Publication Status
Published
Date Publish Online
2018-04-25