The name "Blue Heart" seems to have been inspired by the rare deep blue color of the diamond and it's extraordinarily beautiful heart-shaped cut, that makes it perhaps the world's prettiest blue diamond. The "Blue Heart" diamond is sometimes known as the "Unzue" diamond, after the Argentinean woman Mrs. Unzue who owned the diamond for 43 years, having purchased it from Cartier's in 1910, two years after it's discovery. The diamond is also mistakenly referred to as the "Eugenie Blue," after Empress Eugenie of France, the empress consort of Napoleon III (1852-1870), but she could never have owned this diamond because it was discovered only in 1908.