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15 Cards in this Set
- Front
- Back
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Diamond and graphite are both made of
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carbon |
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The large, stable parts of the earth’s continental crust are called |
cratons |
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During emplacement, if diamonds are exposed to high temperature along with decreased pressure for a long period, they will
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convert to graphite. |
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The first authenticated diamond discovered in South Africa is named the
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Eureka |
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How far beneath the earth’s surface do diamonds form?
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90 to 120 miles (140 to 190 kilometers)
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Diamond is hard and graphite is soft because of the difference in
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the way their atoms fit together.
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Diamonds were delivered to the earth’s surface as recently as
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20 million years ago. |
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Before arriving at the earth’s surface, diamonds might remain in the mantle for as long as a few
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hundred million years.
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The three main components of the earth are the crust, mantle, and
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core |
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Most of the world’s kimberlite pipes
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do not contain diamonds in profitable quantities.
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The correct conditions for diamond formation exist under
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cratons |
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Scientists have found that diamonds form in two types of rocks, called
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peridotite and eclogite.
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Subduction occurs when
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two of the earth’s crustal plates collide.
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The deep vertical formations through which diamonds traveled to the surface are called
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pipes |
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The proper environment for diamond formation includes the right temperature, pressure and
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the availability of carbon.
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