Seven samples of ferromanganese nodules were analyzed using particle-induced X-ray emission technique (PIXE). All the samples were air-dried, crushed, and ground to a fine particle size (<100 mesh). Between 200 and 300 mg of each of the nodule samples was digested in a Teflon-lined stainless steel vessel with a 3:3:1 mixture of Ultrex HNO3, HF, and HC1 at 110 "C for several hours. A Nuclepore filter was impregnated with three 100-µL aliquots of the resulting solution and the thin target sandwiched between Kapton. The samples were irradiated with a 1-MeV proton beam for 1/2 h and the low-energy X-ray spectrum (0-10 keV) was collected. The high-energy (5-35 keV) emission spectrum obtained with a 2-MeV proton beam was collected for 1 h with a 0.004-in. A1 filter. The elemental concentrations present in the thin targets were calculated from the X-ray efficiency curves as described for the standard reference materials.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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 tables is digitized from Table IV - A, pp. 2200 of the linked publication.The data presented result from an average over 5 replicate analyses