The samples were collected from R/V "Yaquina" at 13°40'S, 102°8'W during cruise YALOC-73 of Oregon State University. The Mn nodules were sorted by morphological type before analysis. The Mn nodules and crust were analysed for REE by mixed-solvent ion exchange and mass spectrometric isotope dilution. Isotope analyses were performed on an A.E.I. MS5 mass spectrometer. The determinations of Fe, Mn, Co, Cu, Ni (atomic absorption spectrophotometry) and P (colorimetry) were made on the leachate from 0.1 M HCl.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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 Table 1, pp. 164-165 of the related publication.