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  2. Ultramafic rock - Wikipedia

    en.wikipedia.org/wiki/Ultramafic_rock

    Ultramafic rock. Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta -igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are composed of usually greater than 90% mafic minerals (dark colored, high magnesium and iron ...

  3. Komatiite - Wikipedia

    en.wikipedia.org/wiki/Komatiite

    Komatiite / koʊˈmɑːtiˌaɪt / is a type of ultramafic mantle -derived volcanic rock defined as having crystallised from a lava of at least 18 wt% magnesium oxide (MgO). [1] It is classified as a 'picritic rock'. Komatiites have low silicon, potassium and aluminium, and high to extremely high magnesium content.

  4. Mafic - Wikipedia

    en.wikipedia.org/wiki/Mafic

    A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium -rich varieties of plagioclase ...

  5. Serpentinite - Wikipedia

    en.wikipedia.org/wiki/Serpentinite

    Closeup view about 30 cm × 20 cm (12 in × 8 in). Serpentinite is a metamorphic rock composed predominantly of one or more serpentine group minerals formed by near to complete serpentinization of mafic to ultramafic rocks. Its name originated from the similarity of the texture of the rock to that of the skin of a snake. [1]

  6. Peridotite - Wikipedia

    en.wikipedia.org/wiki/Peridotite

    Peridotite. Peridotite (US: / ˈpɛrɪdoʊˌtaɪt, pəˈrɪdə -/ PERR-ih-doh-tyte, pə-RID-ə-) is a dense, coarse-grained igneous rock consisting mostly of the silicate minerals olivine and pyroxene. Peridotite is ultramafic, as the rock contains less than 45% silica. It is high in magnesium (Mg 2+), reflecting the high proportions of ...

  7. Dunite - Wikipedia

    en.wikipedia.org/wiki/Dunite

    Dunite (/ ˈduːnaɪt, ˈdʌnaɪt /), also known as olivinite (not to be confused with the mineral olivenite), is an intrusive igneous rock of ultramafic composition and with phaneritic (coarse-grained) texture. The mineral assemblage is greater than 90% olivine, with minor amounts of other minerals such as pyroxene, chromite, magnetite, and ...

  8. Volcanogenic massive sulfide ore deposit - Wikipedia

    en.wikipedia.org/wiki/Volcanogenic_massive...

    Mineral exploration companies are exploring for seafloor massive sulfide deposits; however, most exploration is concentrated in the search for land-based equivalents of these deposits. The close association with volcanic rocks and eruptive centers sets VMS deposits apart from similar ore deposit types which share similar source , transport and ...

  9. Lateritic nickel ore deposits - Wikipedia

    en.wikipedia.org/wiki/Lateritic_nickel_ore_deposits

    The nickel (+/- cobalt) metal is liberated from such minerals only at low pH and high temperatures, generally in excess of 250 °C. The advantages of HPAL plants are that they are not as selective toward the type of ore minerals, grades and nature of mineralisation. The disadvantage is the energy required to heat the ore material and acid, and ...