Sample Location All seven samples (collected by S. Moorbath) are from well-localised garnet-mica schist horizons in the eastern sector of the Isua greenstone belt, close to various expedition base camps of 1978, 1993 and 1997. No GPS coordinates are available, but the sample sites are easily located on aerial photographs, and on the geological map of the Isua region published by the Geological Survey of Greenland in 1986 (Bull. Gronlands geol. Unders. No.154). Further details of sample localities can be obtained from S. Moorbath (Oxford). Note that sample SM/GR/97/22 was collected from the same (complex) outcrop as sample IE 715 28 (collected by R.F.Dymek), which was used by Jacobsen and Dymek (J. Geophys. Res. 93, 1988, 338-354) for 728-732) for 147 146 Sm-143Nd studies, and by Harper and Jacobsen (Nature 360, 1992, Sm-142Nd studies, from which the latter authors claim to have discovered the presence of excess 142Nd. Sample description SM/GR/93/13 Porphyritic garnet set in equigranular groundmass of plagioclase, biotite, quartz, muscovite, epidote, zoisite, tourmaline. SM/GR/93/33 Banded, granular, intergrown aggregate of garnet, plagioclase, quartz, hornblende, biotite, with minor ore and calcite. SM/GR/93/57 Foliated schist with porphyritic garnet, quartz, plagioclase, biotite, muscovite, epidote, tourmaline. SM/GR/93/76 Porphyritic garnet, large staurolite grains, with strongly foliated groundmass of quartz, muscovite, plagioclase. SM/GR/97/22 Equigranular, slightly foliated schist, with quartz, plagioclase, biotite, calcite, tourmaline, apatite. 248484 Porphyritic garnet (not abundant) set in foliated, folded groundmass of quartz, plagioclase, biotite, muscovite. 248443 Identified in the field as garnet-hornblende-mica-feldspar schist, but thin section currently unavailable.