Chemical analyses were made on one hundred and forty five powder samples taken from defined parts of manganese nodules retrieved during the GH80-5 campaign of the R/V Hakurei-Maru in the Pacific Ocean. The analyzed parts were prescribed according to external and internal morphology: samples from nodule tops, bottoms, outer layer, inner parts, and entire nodules were prepared. This description of analysed parts proved important in understanding the relationship between mineral and chemical compositions as compared with previous bulk analyses. More than one samples were selected from each station as representatives of the stations. Samples have been powdered and dried at 110° C. Seven metal elements have been determined by atomic absorption spectroscopy. Water content has been determined both for H2O+ by the Penfield method (gravimetric) and for H2O- as the drying loss at 100°C.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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 XV-1, pp. 244-248 of the related publication.