Lithium Isotope Materials
A high variability in lithium isotopic compositions of about 80 ‰ is observed in naturally occurring terrestrial materials, primarily due to the very large difference in mass between 6Li and 7Li. For reporting δ(7Li), it is recommended that NIST RM 8545 lithium carbonate (LSVEC) be used, which was prepared by Harry Svec. In comparison to average seawater, LSVEC is depleted in 7Li by approx. 30 ‰.
Name | Material | δLSVEC(7Li) |
---|---|---|
LSVEC (NIST RM 8545) | Li2CO3 | 0 ‰ * |
IRMM-016 | Li2CO3 | 0.14(20) ‰ |
NRC NASS-5 | seawater | 30.63(44) ‰ |
OSIL IAPSO | seawater | 30.84(19) ‰ |
IRMM BCR-403 | seawater | 30.8(6) ‰ |
NIST SRM 610 | silicate glass | 32.50(2) ‰ |
NIST SRM 612 | silicate glass | 31.2(1) ‰ |
NIST SRM 614 | silicate glass | 20.5(1) ‰ |
BCR-2 | silicate glass | ca. 3.5 ‰ ** |
JA-1 | andesite | ca. 5.7 ‰ ** |
JB-2 | basalt | ca. 4.5 ‰ ** |
JB-3 | basalt | 3.94(29) ‰ |
BHVO-1 | basalt | ca. 5.2 ‰ ** |
BHVO-2 | basalt | 4.7(2) ‰ |
Name | Material | δLSVEC(7Li) |
* Exact value defining the δ(7Li) LSVEC scale.
** See the Assessment of international reference materials for isotope-ratio analysis for more details.
Values in parenthesis are expanded (k = 2) uncertainties applicable to the last digits. The values listed in this table are compilation and are not necessarily CIAAW recommendations.
Citation
W.A. Brand et al
Assessment of international reference materials for isotope-ratio analysis
Pure and Applied Chemistry 86, 425-467 (2014)
CIAAW recommends that authors discontinue reporting δ(6Li) values in terms of n(6Li)/n(7Li). The full recommendation appears in Atomic weights of the elements 1995 by T.B. Coplen, Pure Appl. Chem. 68 2339-235 (1996).