Four hundred and twenty kilograms of manganese nodules were recovered at Station U205 in the Tasman Sea. They were sorted by size class. Representative subsets for each size class were chemically analysed and their avearge composition is presented in the published table. Samples were alaysed by X-ray fluorescence spectrometry. For this purpose, samples were ground to 80 mesh, dried at 105°C for at least 24 hours and fused with "Spectromelt A 12" (Merck 11802, containing 66% lithium tetraborate and 34% lithium metaborate). To prepare glass beads, 1 g of Mn nodule materail was mixed with 1 g of flux and heated in a RF-furnace for about 5 minutes.
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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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. 490 of the related publication.