Unlike most other rocks that are formed in Earth's crust, diamonds are formed deep beneath Earth's surface. Their ability to reveal the chemical and mineralogical nature of Earth's mantle makes them a valuable resource for geologists seeking to uncover the many mysteries of Earth's interior. However, the task is challenging due to the diamonds' tight internal bond, which makes the stones difficult to date. In this video segment from Nature, geologist Larry Taylor explains the geological value of diamonds.
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