The Portuguese Diamond at 127.01 carats is the largest faceted diamond in the National Gem Collection. It was graded by the Gemological Institute of America (GIA) as M in color and VS-1 in clarity, with very strong blue fluorescence. Its near flawless clarity and unusual octagonal emerald cut make it one of the world's most magnificent diamond gems. The apparent cloudiness in the stone is actually blue fluorescence that is so intense it shows up even under incandescent lights. In 1928, Peggy Hopkins Joyce purchased the diamond from Black, Starr & Frost, mounted on a diamond-studded platinum choker. The jewelry firm indicated that the diamond was found at the Premier Mine, Kimberley, South Africa, in 1910, and that Black, Starr & Frost obtained it shortly after its discovery. In 1951, Harry Winston acquired the Portuguese Diamond from Miss Peggy Hopkins Joyce, a glamour girl of the 1920s. For the next several years it traveled around the country as part of his "Court of Jewels" exhibition. In 1963, the Smithsonian acquired the diamond from Mr. Winston in exchange for 2,400 carats of small diamonds.
Image Number: 95-40410
Catalog Number: G3898
Weight: 127.01 carats
Acquired from Harry Winston in exchange for 2,400 carats of small diamonds
Locality: Premier Mine, Kimberley