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The earth condensed from gas into liquid into solid. Rocks are assumed to be solids and not a fluid part of a melt. Bowens Reaction Series implies that the first rocks on earth would have been Olivine Polymorphs. MgSiO3-perovskite and MgO (periclase) are likely candidates from observations at the Earths Moho. As far as the "rock cycle" goes; these ...


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The answer is simple: The Earth came out of the Sun as a molten ball of magma. It took an age to cool and eventually developed a crust as the magma cooled down. So the first "rocks" on Earth must have been "igneous" (developed from a firey or molten state). In Barberton South Africa, the Barberton Greenstone Belt (BGB) comprises a basal ...


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