Enabling scientific discovery through stable isotope analysis
Reference Materials

List of all reference materials kept in the IsoLab.

Reference
Material
δD
VSMOW
(permil)
δ13C
VPDB
(permil)
δ15N
Air N2
(permil)
Δ17O
VSMOW
(permil)
17Oexcess
VSMOW
(permeg)
δ18O
VSMOW
(permil)
δ34S
VCDT
(permil)

Material
NBS19 1 +1.95 +28.65 limestone
LSVEC 1 -46.6 +3.394 lithium carbonate
NBS18 -5.01 +7.20 limestone
C1 +2.55 +30.41 marble
C2 -48.94 +14.04 calcium carbonate
CQS2 -2.13 +15.16 calcium carbonate
IAEA-NO-3 +4.72-0.2 +25.32 potassium nitrate
USGS34 -1.8-0.1 -27.78 potassium nitrate
USGS35 +2.7+21.6 +56.81 sodium nitrate
USGS34/35mix +0.45+10.75 nitrate mixture
USGS32 6 +180 +25.4 potassium nitrate
IAEA-N-1 6 +0.43 ammonium sulfate
NIST8540 -32.15 polyethylene foil
NIST8542 -10.45 Sucrose
USGS40 -26.39-4.52 L-glutamic acid
USGS41 +37.63+47.57 L-glutamic acid
NIST1547 4 -25.99+1.98 peach leaves
GA1 -28.2-4.6 glutamic acid
GA2 -13.6-5.6 glutamic acid
Salmon -21.311.3 Bristol Bay Sockeye
MAL -26.5-0.4 +8.3Malachite Lake Sediment
IAEA-S-1 2 -0.3silver sulfide
IAEA-S-3 -32.55silver sulfide
NBS-127 +21.1barium sulfate
Ag2S +17.60silver sulfide
ZnS -32.31zinc sulfide
Ba100 +4.59barium sulfate
sulfα5 0.9 sodium sulfate
sulfβ5 2.0 sodium sulfate
sulfε5 7.0 sodium sulfate
VSMOW30 00 Vienna Standard Mean Ocean Water
GISP-190 22-24.8 Greenland Ice Sheet Precipitation Water
SLAP3,7-428 0-55.5 Standard Light Antarctic Precipitation Water
USGS PR-1.3 -1.52 USGS Puerto Rico Water
USGS A1-395 -50.02 USGS Antarctic Water
RW-18.51 +5.16 Evaporatively enriched Seattle Water
PW-41.91 -6.88 Pennsylvania Water
SW-75.49 -10.50 Seattle Water
BW-156.84 -20.12 ITASE / Seattle Water
AW-231.11 -29.83 Antarctic Water
WW-267.44 -33.76 WAIS Water
CW-266.03 -33.64 WDC06A Water NICL 2009
TDW-309.49 -38.75 Taylor Dome Water
WGW-319.48 -39.83 WDC06A Water Last Glacial Period
SVW-316.68 -41.10 Seattle / Vostok Water
VW-438.57 -56.56 Vostok Water
O2 gas 48.4-8.26 Oxygen in compressed gas cylinder

1 - exact values defining the VPDB delta scale
2 - exact value defining the VCDT delta scale
3 - exact values defining the VSMOW delta scale
4 - NOT accepted, merely a guide
5 - Schauer et al. Rapid Commun. Mass Spectrom. 2012, 26, 2151-2157. DOI: 10.1002/rcm.6332
6 - interim consensus values used for AirN2 scale normalization
7 - Schoenemann et al. Rapid Commun. Mass Spectrom. 2013. DOI: 10.1002/rcm.6486

VPDB = 0.97001*VSMOW - 29.99 (from Coplen blue book)

Δ17O is calculated as δ17O - 0.52 * δ18O and are in units of permil.

17Oexcess is calculated as (ln(δ17O/1000+1)-0.528*ln(δ18O/1000+1))*1000000 and are in units of permeg.