A suite of eight glassy rims and six crystalline interiors from pillowed basalts was collected from within the Mid-Atlantic Ridge rift valley between 25°N and 30°N during Trans-Atlantic Geotraverse (TAG) NOAA cruises using the R/V Discoverer. Radiochemical neutron activation analysis has been used to determine Tl, Rb. Cs. Co and Cr. Major element and S analyses of the glasses were determined by electron probe microanalysts of small polished chips of glass.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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. 1306-1307 of the related publication.