Differentiate between alluvial (placer) diamonds and primary diamonds hosted in kimberlite pipes, and state the implication for mining methods.

Differentiate between alluvial (placer) diamonds and primary diamonds hosted in kimberlite pipes, and state the implication for mining methods.

• A. Alluvial diamonds are eroded and deposited in riverbeds and are mined via placer methods, while primary diamonds are in kimberlite pipes requiring open-pit or underground mining and blasting.
• B. Alluvial diamonds are synthetic; primary diamonds are natural.
• C. Alluvial diamonds come from the sea floor; primary diamonds come from riverbeds.
• D. Alluvial diamonds require underground mining; primary diamonds can be mined via surface alluvial.

Answer: (A)