Question: where do the world's diamonds come from

title: Diamond
text: Diamonds are far from evenly distributed over the Earth . A rule of thumb known as Clifford 's rule states that they are almost always found in kimberlites on the oldest part of cratons , the stable cores of continents with typical ages of 2.5 billion years or more . However , there are exceptions . The Argyle diamond mine in Australia , the largest producer of diamonds by weight in the world , is located in a mobile belt , also known as an orogenic belt , a weaker zone surrounding the central craton that has undergone compressional tectonics . Instead of kimberlite , the host rock is lamproite . Lamproites with diamonds that are not economically viable are also found in the United States , India and Australia . In addition , diamonds in the Wawa belt of the Superior province in Canada and microdiamonds in the island arc of Japan are found in a type of rock called lamprophyre . 

Answer: answer: A rule of thumb known as Clifford 's rule states that they are almost always found in kimberlites on the oldest part of cratons , the stable cores of continents with typical ages of 2.5 billion years or more . The Argyle diamond mine in Australia , the largest producer of diamonds by weight in the world , is located in a mobile belt , also known as an orogenic belt , a weaker zone surrounding the central craton that has undergone compressional tectonics .
answer: A rule of thumb known as Clifford's rule states that they are almost always found in kimberlites on the oldest part of cratons, the stable cores of continents with typical ages of 2.5 billion years or more. The Argyle diamond mine in Australia, is located in a mobile belt, a weaker zone surrounding the central craton that has undergone compressional tectonics. In addition, diamonds are found in the Wawa belt of the Superior province in Canada and microdiamonds in the island arc of Japan.