This week, The Gilded Age, a new television series from Downton Abbey creator Julian Fellowes, premiered in the US on HBO. In honor of the long-awaited arrival of the show, I’m going to be showcasing famous jewels from the Gilded Age on selected days over the next several weeks here at The Court Jeweller. We’re kicking things off with a big one: the diamond tiara that belonged to Consuelo Vanderbilt, the American heiress who became Duchess of Marlborough in 1895.