Brussels 22.05.2021 The Sakura diamond a massive 15.81 carat purple-pink internally flawless gemstone is expected to gain between $25-35 million when it goes on sale at Christie’s in Hong Kong on Sunday, May 23. VIDEO: The Sakura diamond — a massive 15.81 carat purple-pink internally flawless gemstone — is expected to fetch between $25-35 million…