How does carbon change into diamonds?

Answer 1

Diamonds are formed deep underground inside the earth's mantle, under intense pressure and extreme heat.

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Answer 2

Diamonds are formed from carbon deep within the Earth's mantle under extremely high pressure and temperature conditions. Over millions of years, the carbon atoms undergo a process of crystallization, forming the strong, tightly packed structure characteristic of diamonds. Through volcanic eruptions or other geological processes, diamonds are brought closer to the Earth's surface, where they can be mined.