The properties of ferromanganese concretions reflect in many ways the marine environment in which they were formed, and points to a variety of probable genetic mechanisms in different environments. There are also chemical and probably mineralogical variations which follow the various growth habits, and are a function of the environment. This report presents morphologic descriptions of the HIG manganese collection. Material described here was collected by the Hawaii Institute of Geophysics and Department of Oceanography during cruises of the R/V MAHI (1968-70), R/V KANA KEOKI (1971-72), and R/V TERITU (1971-72) and during the experimental test of a Continuous Line Bucket nodule retrieval experiment with the Japanese R/V Koyukoyu_Maru_II in 1972.
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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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.