Leaving this annex area we passed through a metal door in an internal compound wall and came into a pleasant lawn area, in the middle of which was a small structure that was used by the residents as a sun room.

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In the middle of the compound, there is a giant cage with huge metal grilles.

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It was little more than a razor wire and mesh compound of cages, protected from the elements by a metal roof.

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By combining an artist and scientific quest, the two professors at Michigan State University found that a certain type of metal-loving bacteria can transform high amounts of the toxic chemical compound gold chloride from a liquid into solid 24-karat gold.

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Yes that's right, the base metal element lead, Pb, or more exactly the lead-based chemical compound Pb(CH2CH3)4 added to petrol to make car engines run more smoothly.

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