Carats & Coils The work of Italian jewelry designer Roberto Demeglio was introduced to U.S.  clients of Beny Sofer in New York City just earlier this year, and Sofer has already placed the line in 70 stores nationwide. Signature Demeglio looks include ­diamond-accented ceramic numbers that resemble dominoes and patented stretchable bracelets and rings that are drenched in diamonds, like the wide cuff pictured here. Pieces are made in 18k gold and the stretchable styles feature a patented stainless-steel coil system that’s concealed beneath the bling, allowing pieces to “slide on easily, stay on firmly, and never lose elasticity,” according to the company. Moving On For nearly 80 years, De Beers sorted its diamonds in an ornate building on London’s ­Charterhouse Street. No more. De Beers’ Botswana building On Aug. 14, the De Beers Group announced that its worldwide d