First is a core of rock, then clay and lastly soil, topped with grass seed that will withstand being walked on.

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The Antarctic Geological Drill (ANDRILL) team, as they're known, has just completed its second field-season here, retrieving an 1, 100-metre core of rock and sediment.

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Unlike any other asteroid known today, Vesta has an iron core surrounded by layers of mantle rock and crust, similar to Earth and Mars, preliminary gravity and density measurements suggest.

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France is considered a rock solid, core member of the euro zone, and its troubles are of great concern.

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Tired of playing in rock and cover bands, core members David Hidalgo, Louie Perez, Cesar Rojas, and Conrad Lozaron learned folk songs from musicians in East L.A., and took trips to Mexico to do research.

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In its Fruta del Norte site a drill core showed a rich 32 troy ounces of gold per ton of rock.

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The heat that keeps the core of the earth molten is primarily radioactive decay -it is what makes rock into liquid lava.

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