Greenstone belt
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Greenstone belts are zones of variably metamorphosed mafic to ultramafic volcanic sequences with associated sedimentary rocks that occur within Archaean and Proterozoic cratons between granite and gne
Kilimafedha greenstone belt in Tanzania
Metamorphosed pillow lava from the Ishpeming Greenstone Belt in Michigan
Weathered Precambrian pillow lava in the Temagami greenstone belt on the Canadian Shield
Ultramafic rock
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Ultramafic rocks are igneous and meta-igneous rocks with a very low silica content, generally >18% MgO, high FeO, low potassium, and are usually composed of greater than 90% mafic minerals. Earth's ma
Peridotite, a type of ultramafic rock
Melilitite from Hohenstoffeln (Hegau)