The largest diamond ore deposit in the world is generally considered to be the Jwaneng diamond mine in Botswana. Operated by Debswana, a joint venture between the Botswana government and De Beers, Jwaneng is known as "the richest diamond mine in the world" in terms of the value of diamonds produced, not the sheer size of its ore deposit.

If we talk about size or geological significance, the Siberian Mirny Mine (Mir Mine) in Russia and the Orapa mine in Botswana are also worth mentioning. Here is more detailed information about some key deposits:

1. Jwaneng Mine (Botswana)

• Type: Open-pit.
• Known for: High-value diamond production.
• Annual Output: Around 10–15 million carats.
• Geological Features: The deposit is located in kimberlite pipes, volcanic formations that bring diamonds from deep within the Earth's mantle.

2. Orapa Mine (Botswana)

• Type: Open-pit.
• Known for: Being one of the largest diamond mines by area.
• Geological Features: Similar to Jwaneng, it consists of kimberlite pipes.
• Annual Output: Approximately 11–12 million carats.

3. Mirny Mine (Russia)

• Type: Former open-pit, now underground.
• Known for: Huge deposit size and being one of the first diamond mines in Russia.
• Geological Features: Located in kimberlite pipes within the Siberian terrain.
• Historical Output: Significant during its peak years but no longer a leading producer.

4. Argyle Mine (Australia) (Now closed)

• Type: Open-pit and underground.
• Known for: Producing most of the world's pink diamonds.
• Annual Output: Up to 8 million carats before its closure in 2020.
• Geological Features: Unique lamproite host rock, different from traditional kimberlite deposits.

Largest Kimberlite Pipe:

The Udachnaya pipe in Russia is one of the largest known kimberlite pipes by size. Although it is not as economically valuable as Jwaneng or Orapa, its geological scale is remarkable.