World's oldest diamonds are?

Diamonds are usually one or two billions years old, but what about world's oldest diamonds, where do they come from, which part of the world is their home? In 2006 scientists discovered diamond fields in Canada’s Northwest Territories and thought they have found the oldest diamonds on Earth as these diamonds were formed 3.5 billion years ago in an era called the Archean, this was time when Earth was forming its first continents. But these diamonds didn't carried title "world's oldest diamonds" for a very long time. In fact their fame lasted just one year when the 4 billion year old diamonds were found trapped inside zircon crystals from the Jack Hills region, few hundreds kilometres north of the Western Australian capital Perth.