One of the world’s most outstanding examples of February’s birthstone is the 96-carat heart-shaped stunner at the center of the "Amethyst Heart Brooch," an Edwardian-period piece that was donated to the Smithsonian in 1973 by philanthropist Miriam Hubbard Morris. Exhibiting a deep, rich purple color, the Brazilian-sourced amethyst is surrounded by diamonds in a mounting […]