What country produces the best quality diamonds?

I'm curious to know, when it comes to diamonds, which country is renowned for producing the finest quality stones? Is there a specific region or mine that consistently delivers exceptional diamonds, or is it a matter of debate among experts? What factors contribute to the high quality of diamonds from a particular country, and how do these diamonds differ from those sourced elsewhere? It would be fascinating to learn more about the intricacies of diamond production and the countries that excel in this field.