Own a piece of Tiffany & Co.’s storied history at 15 Union Square West. 15 Union Square West is a rare gem, with a history deeply embedded in New York City’s post-Civil War transformation. In 1870, Tiffany & Company chose this location for its first headquarters, commissioning a cast-iron building designed by John Kellum that The New York Times called “a palace of jewels.” For over three decades,...