The Kennecott nodule standard GRLD-126 was run with several batches of the nodule structure zone samples in order to check the precision of the atomic absorption analyses. Using the standard deviation as a measure of precision, copper values are the most reproducible (+- 4% from the mean), with manganese (+- 5%), nickel (+- 6%), iron (+- 7%) and cobalt values (+- 14%) being successively less precise. The possible variability of the cobalt values is such that subtle differences in cobalt content between many oxide crusts and subcrusts may not be real.

From 1983 until 1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions. At the time it was the most extended data compilation on ferromanganese deposits world wide. Initially published in a proprietary format incompatible with present day standards it was jointly decided by AWI and NOAA to transcribe this legacy data into PANGAEA. This transfer is augmented by a careful checking of the original sources when available and the encoding of ancillary information (sample description, method of analysis...) not present in the NOAA-MMS database.This dataset represents the digitized version of App. N (cont.), p. 312 of the related publication.