Filter real minerals by where they form — beneath the seafloor or across the continents.
Manganese, iron oxides
Smaller ferromanganese concretions form on continental shelves and lake bottoms; commercially marginal but geochemically important.
Ilmenite, rutile, zircon, monazite, gold
Wave and current sorting concentrates dense minerals into 'black sand' layers along beaches and inner shelves worldwide.
Diamond crystals in marine gravels
Diamonds eroded from inland kimberlites are carried by rivers to the sea and concentrated in gravel beds along continental shelves.
Iron-potassium phyllosilicate ((K,Na)(Fe,Al,Mg)₂(Si,Al)₄O₁₀(OH)₂)
Distinctive green marine sand grains formed slowly on continental shelves under low-oxygen conditions, used as a slow-release fertilizer and water softener.
Calcium phosphate
Sedimentary deposits formed on continental shelves and slopes under upwelling currents, used as a primary source of agricultural phosphate.
Methane locked in water-ice cages
Ice-like solids stable under cold high-pressure conditions in continental margin sediments, holding vast reserves of natural gas.
Barium sulfate (BaSO₄)
Pale, dense crystalline deposits formed at cold seeps and hydrothermal margins where barium-rich fluids meet sulfate-rich seawater.
Halite (NaCl), gypsum, anhydrite, potash
Buried evaporite layers rise as salt diapirs through overlying sediments, sometimes breaching the seafloor and feeding hypersaline brine pools.
Cobalt, manganese, iron, rare earths
Hard pavements that coat seamounts and ridge flanks, accumulating at just millimeters per million years and enriched in critical battery metals.
Goethite, hematite, ferrihydrite (Fe oxyhydroxides)
Low-temperature 'diffuse' vents drape the seafloor in vivid orange and ochre iron-oxide crusts, often microbially mediated.
Tellurium, cobalt, manganese, iron oxides
Seamount crusts uniquely enriched in tellurium — a rare element critical for high-efficiency thin-film solar cells.
Copper, zinc, gold, silver, lead
Mineral chimneys deposited around active hydrothermal vents along mid-ocean ridges, where superheated fluids meet cold seawater.
Amorphous silica (SiO₂·nH₂O) with metal sulfide traces
Pale, lacy silica spires deposited by lower-temperature vents, often hosting unique microbial life and trace precious metals.
Manganese & iron oxides cementing seafloor sediment
Continuous metallic crusts that pave entire stretches of abyssal seafloor — sometimes growing right around the polymetallic nodule fields.
Yttrium, dysprosium, neodymium, lanthanides in deep-sea clay
Deep-sea clays in the central Pacific and Indian Oceans hold rare earth concentrations rivaling — and sometimes exceeding — the world's richest land deposits.
Manganese, nickel, copper, cobalt
Potato-sized concretions scattered across abyssal plains (notably the Clarion–Clipperton Zone), grown over millions of years from precipitated metals.
