It’s been quite a month since 24 Karat weekend, with a trip to India, a few days with jewelry friends in Park City, Utah, and a whirl through Arizona, from the Centurion show in Scottsdale to the American Gem Trade Association GemFair in Tucson.It had been five years since I visited Mumbai (blame the recession!), and I was blown away by the changes. From my window in the new Shangri-La Hotel, I could see the fast-transforming neighborhoods of Worli and Parel and the Sea Link elevated freeway bridge connecting them to Bandra, home to the new Bharat Diamond Bourse.The diamond dealers there were more bullish about business in the United States than I’ve heard for years. They’re also thrilled with their new offices and are excited for more Americans to visit. A highlight was our lunch in the beautiful glass pavilion atop the office building of the Gitanjali Group. Our host, chairman Me