Five of 34 dredge hauls taken in the Atlantic Ocean recovered a material tentatively described on shipboard as a salmon-colored clay. X-ray diffraction analysis showed the clay material to consist principally of palygorskite. Occurring with the palygorskite are quartz, calcite, and dolomite. It is suggested that the palygorskite (and sepiolite) is the result of chemical precipitation brought about by the reaction of hydrothermal solutions with sea water.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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: Bowles, F A; Angino, E A; Hosterman, J W; Galle, O K (1971): Precipitation of deep-sea palygorskite and sepiolite. Earth and Planetary Science Letters, 11(1-5), 324-332