Emerald is the most valuable variety of the mineral beryl. Primarily green, it may also display tints of yellow or blue. Not enough green, and the stone will be classified as green beryl. Too much blue, and it will be called an aquamarine. Thus, the more pure green color the emerald displays, the more valuable it is. Its color is caused by impurity atoms of either chromium or vanadium, which are incorporated into beryl crystals as they grow. The 858 carat uncut Gachala Emerald was found at the Vega de San Juan mine in Gachala, Colombia, in 1967. Rarely are emerald crystals of such size and superb color preserved; they are usually cut into gems. Harry Winston donated the Gachala Emerald to the Smithsonian in 1969.
The stunning Mackay Emerald was mined in Muzo, Colombia. The largest cut emerald in the National Gem Collection, it is set in a pendant of diamonds and platinum and was designed by Cartier. The art deco style necklace was a wedding gift in 1931 from Clarence Mackay to his wife Anna Case Mackay, who was a prima donna at the New York Metropolitan Opera from 1909 to 1920. The emerald weighs 167.97 carats and is set in platinum with 35 emeralds and 2,191 colorless brilliant and step cut diamonds.
This superb 75.47carat Colombian emerald was once the property of Abdul Hamid II, Sultan of the Ottoman Empire (1876-1909), who wore it on his belt buckle. Tiffany & Co. acquired the emerald in 1911 and initially set it into a tiara. In 1950, it was mounted in its current brooch setting. Mrs. Janet Annenberg Hooker purchased the brooch from Tiffany in 1955, and in 1977 she donated it to the Smithsonian Institution. The Hooker Emerald is a beveled square-cut gem that exhibits exceptional color and clarity for an emerald of its size. In its platinum setting it is surrounded by 109 round and 20 baguette cut diamonds, totaling approximately 13 carats.
The Spanish Inquisition Necklace consists of two strands of antique-cut diamonds and emeralds to which a lower pendant and upper chain containing modern, brilliant-cut diamonds were added. The necklace contains 374 diamonds and 15 emeralds. The emeralds undoubtedly came from Colombia, while the diamonds were obtained from India, the only source of diamonds until 1723. The large, central, barrel-shaped emerald weighs approximately 45 carats. Due to its rich color and exceptional clarity, it is one of the world's finest emeralds. The stones were probably cut in India in the seventeenth century, making them the earliest cut gems in the National Gem Collection. Although the origin of the necklace's name is unknown, it was probably created this century in reference to its similarity to other jewelry of the period. However, according to legend, at least a portion or a variation of the necklace belonged to Spanish royalty and was later worn by ladies of the French court. The necklace was purchased by the Maharaja of Idore in the early twentieth century. In 1948, Harry Winston purchased the necklace from the Maharaja's son. The necklace then became part of Winston's "Court of Jewels" traveling exhibition. Cora Hubbard Williams of Pittsburgh, Pennsylvania bought the necklace from Winston in 1955 and donated it to the Smithsonian Institution in 1972.