Examen
GIA DIAMONDS/DIAMOND GRADING 4-6
- Cours
- Établissement
Diamonds were delivered to the earth's surface as recently as A. 20 billion years ago. B. 20 million years ago. C. 1 million years ago. D. 10,000 years ago. - Answer-B. 20 million years ago. The three main components of the earth are the crust, mantle, and A. core. B. center. C. s...
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