Some manganese samples (two crusts and two nodules) dredged around 1,000 m depth on the southern slope of the Tuamotu Archipelago have shown five associations of calcareous nannofossils, which are either included in or printed into the cortex and the nucleus. The location and the age of these associations let us reconstitute the full story of the samples. The growth of the incrustations occurred mainly during two periods: the first one between the middle Eocene and the basal Oligocene, the second one between the upper Pliocene and the Recent.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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

Supplement to: Janin, Marie-Christine (1985): Biostratigraphie de concrétions polymétalliques de l'archipel des Touamotou, fondée sur les nannofossiles calcaires = Biostratigraphy of polymetallic concretions of the Tuamotu Archipelago, based on the calcareous nannofossils. http://bsgf.geoscienceworld.org/content/I/1/79.full.pdf+html, Bulletin de la Societe Geologique de France, 1(1), 79-87