Meta-sediments from Isua, West Greenland were analyzed by instrumental thermal neutron activation analysis (ITNAA). These sediments are chemical precipitates having some layers of remarkably high Cr content. The latter were compared to Cr poor layers. It turned out that the Cr enriched layers had higher Ir and Ni contents than the samples from the Cr poor layers. Compared to phanerozoic samples the highest Ir contents are not extraordinarily higher than in a modern sediment, and the Cr poor layers, representing more or less phanerozoic shale. From the cratering record of the Moon one can assume a similar cratering of the Earth at about the time when the Isua rocks were formed.