Bottom dredging during the KK84 campign of the R/V Kana Kenoki recovered numerous ferromanganese crusts on a large variety of substrate (basalt, volcanics, limsetone and phosphorite). These deposits were sampled using hard substrate coring device. The retrieved part was air-dried at 110°C and reduced to powder. One split was dissolved by acid-pressure digestion with concentrated, ultrapure HCI-HNO3-HF and the dissolved residue was analysed for major and selected minor constituents by atomic absorption spectrophotometry (AAS) using a Perkin-Elmer Model 603 doublebeam spectrophotometer. Loss-on-ignition (LOI) determinations were also carried on the duplicate splits for 30 min at 1000°C in a muffle furnace.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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 3, pp. 453 of the related publication.