It's a well-known fact that when it comes to assessing diamonds, the greatest attention is paid to the four Cs; colour, clarity, cut, and carat weight. There is, however, a fifth C that has emerged over the past two decades and become just as much of a priority for today's educated and ethical jewellery buyers: conscience. For a global luxury jeweller as selective as Tiffany & Co. who famously accept just 0.04 percent of the world's gem-grade diamonds, acquiring high-quality, conflict-free diamonds with integrity might sound like an additional challenge, but when it comes to diamond traceability, it's one they've embraced entirely. Anisa Kamadoli Costa – Chairman and President of The Tiffany & Co. Foundation and Chief Sustainability Officer at Tiffany & Co.