Could a greenish stone the size of a coconut be the world`s largest diamond? The BBC reports that a shareholder in an unnamed mine in South Africa has found the stone shown here. The stone is said to be about 7,000 carats, making it around double the size of the famous Cullinan Diamond. There is some question over whether the stone is a diamond. Brett Jolly, a spokesperson for the company, has said that the stone was taken to a bank vault in Johannesburg and would undergo tests.

So far the only evidence of the stone is a low resolution photo showing a stone that could be anything, another type of crystal or even glass. Not revealing where a stone of this size is found is common for security purposes. If this stone is genuine, it will be one of the most amazing finds in recent times.