Table of Contents

    In the Area there are three main types of ore deposits, namely:

    1. Polymetallic nodules,
    2. Polymetallic sulphides,
    3. Cobalt-rich ferromanganese crusts.

    Polymetallic nodules

    These nodules, also known as manganese nodules, are found in lakes, shallow waters and on the ocean floor, in places with extremely low sedimentation rates. They consist mainly of iron and manganese silicates and hydroxides, but also contain small amounts of nickel, copper and cobalt.

    The richest deposits are located in the Clarion-Clipperton Fracture Zone (west of Mexico), in the Central Indian Ocean Basin and the Basin of Peru. Polymetallic nodules grow extremely slowly, with a rate of up to 10 mm per million years.

    Polymetallic sulphides

    These deposits of sulphurous minerals of hydrothermal origin occur in two forms, namely as hydrothermal vents, whether or not extinguished, or as submarine massive sulphide deposits in the vicinity of these hydrothermal vents. They consist mainly of copper and zinc ores, but also contain lead, gold and silver.

    Cobalt-rich ferromanganese crusts

    These deposits, also known as manganese crusts, occur in waters between 400 m and 5,000 m in areas with a large volcanic activity, where the flow is too strong for the deposition of loose sediments. They are formed by precipitating metals from seawater on a hard surface and, in general, have a composition that is comparable to polymetallic nodules. However, they contain higher concentrations of cobalt, platinum and rare earth elements.

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    Last update
    15 December 2025