Amethyst is a violet variety of quartz. The name comes from the Koine Greek αμέθυστος amethystos from α- a-, "not" and μεθύσκω methysko / μεθώ metho, "intoxicate", a reference to the belief that the stone protected its owner from drunkenness. Ancient Greeks wore amethyst and carved drinking vessels from it in the belief that it would prevent intoxication.
A gemstone is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments. However, certain rocks and occasionally organic materials that are not minerals are also used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity and notoriety are other characteristics that lend value to gemstones.
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminium oxide (α-Al2O3) with trace amounts of elements such as iron, titanium, chromium, vanadium, or magnesium. The name sapphire is derived via the Latin "sapphirus" from the Greek "sappheiros", which referred to lapis lazuli. It is typically blue, but natural "fancy" sapphires also occur in yellow, purple, orange, and green colors; "parti sapphires" show two or more colors. Red corundum stones also occur, but are called rubies rather than sapphires. Pink-colored corundum may be classified either as ruby or sapphire depending on locale. Commonly, natural sapphires are cut and polished into gemstones and worn in jewelry. They also may be created synthetically in laboratories for industrial or decorative purposes in large crystal boules. Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of special-purpose solid-state electronics such as integrated circuits and GaN-based blue LEDs. Sapphire is the birthstone for September and the gem of the 45th anniversary. A sapphire jubilee occurs after 65 years.
The Hope Diamond is a 45.52-carat (9.104 g) diamond originally extracted in the 17th century from the Kollur Mine in Guntur, India. It is blue in color due to trace amounts of boron. Its exceptional size has revealed new information about the formation of diamonds.
Amateur geology or rock collecting is the non-professional study and hobby of collecting rocks and minerals or fossil specimens from the natural environment. In Australia, New Zealand and Cornwall, the activities of amateur geologists are called fossicking. The first amateur geologists were prospectors looking for valuable minerals and gemstones for commercial purposes. Eventually, however, more people have been drawn to amateur geology for recreational purposes, mainly for the beauty that rocks and minerals provide.
The Logan Sapphire is a 422.98-carat (84.596 g) sapphire from Sri Lanka. One of the largest blue faceted sapphires in the world, it was owned by Sir Victor Sassoon and then purchased by M. Robert Guggenheim as a gift for his wife, Rebecca Pollard Guggenheim, who donated the sapphire to the Smithsonian Institution in 1960. The sapphire's name is derived from Rebecca's new surname after she later married John A. Logan. It has been on display in the National Gem Collection of the National Museum of Natural History in Washington, D.C., since 1971. It is a mixed cushion-cut sapphire, approximately the size of a large chicken egg, and set in a silver and gold brooch surrounded by 20 round brilliant-cut diamonds.
The Eagle Diamond is a gemstone discovered in Eagle, Wisconsin in 1876 that was about 16 carats. It was found on a hillside about 30 feet below the surface in glacial till while digging a well. It was one of more than a dozen rare gems stolen in a heist from the American Museum of Natural History in 1964 and remains missing to this day.
The Star of Bombay is a 182-carat (36.4-g) cabochon-cut star sapphire originating in Sri Lanka. The violet-blue gem was given to silent film actress Mary Pickford by her husband, Douglas Fairbanks. She bequeathed it to the Smithsonian Institution. It is the namesake of the popular alcoholic beverage Bombay Sapphire, a British-manufactured gin.
George Frederick Kunz was an American mineralogist and mineral collector.
John Francillon (1744–1816) was a jeweler and lapidary, an English naturalist and an entomologist of Huguenot descent.
The Bismarck Sapphire Necklace is a sapphire necklace designed by Cartier, Inc. in 1935. As of 2010, the necklace is on display between the Hall Sapphire and Diamond Necklace and the Logan Sapphire in the Janet Annenberg Hooker Hall of Geology, Gems, and Minerals at the Smithsonian Institution's National Museum of Natural History in Washington D.C., United States. It is named after Countess Mona von Bismarck, who donated the piece to the Smithsonian in 1967. The sapphire itself was mined in Burma, and was purchased by the Countess in Sri Lanka in 1926 during her honeymoon with Harrison Williams.
Murph the Surf, also known as Live a Little, Steal a Lot, is a 1975 film based on a jewel burglary involving the surfer Jack Roland Murphy, who had the nickname "Murph the Surf". Starring Robert Conrad and Don Stroud, it was directed by Marvin J. Chomsky. The New York Times edition of October 20, 2019 revisited the true story of Jack Murphy's theft of the irreplaceable gemstones from a poorly guarded Museum of Natural History.
The Star of Artaban is a 287–carat cabochon-cut star sapphire currently located at the Smithsonian National Museum of Natural History. Its origin is somewhat obscure but it is believed to come from Sri Lanka. Unlike some other sapphires, it is not transparent and is of a milky blue colour. It was donated by an anonymous member of the Georgia Mineral Society in the 1941–1943 time period.
The Star of Asia is a large, 330 carats (66 g) cabochon-cut star sapphire currently located at the Smithsonian National Museum of Natural History. It is noted for its significant size and is considered to be one of the largest of its type. Adding to its aesthetic value are its rich blue colour and clear star, formed from three intersecting rutile striations.
Yogo sapphires are blue sapphires, a colored variety of corundum, found in Montana, primarily in Yogo Gulch in Judith Basin County, Montana. Yogo sapphires are typically cornflower blue, a result of trace amounts of iron and titanium. They have high uniform clarity and maintain their brilliance under artificial light. Because Yogo sapphires occur within a vertically dipping resistive igneous dike, mining efforts have been sporadic and rarely profitable. It is estimated that at least 28 million carats of Yogo sapphires are still in the ground. Jewelry containing Yogo sapphires was given to First Ladies Florence Harding and Bess Truman; in addition, many gems were sold in Europe, though promoters' claims that Yogo sapphires are in the crown jewels of England or the engagement ring of Princess Diana are dubious. Today, several Yogo sapphires are part of the Smithsonian Institution's gem collection.
The Star of Adam is an oval-shaped blue star sapphire, currently the largest star sapphire in the world. It weighs 1,404.49 carats. Prior to its discovery, the Black Star of Queensland, weighing 733 carats (146.6 g), was the largest star sapphire gem in the world.
The Allison and Roberto Mignone Halls of Gems and Minerals are a series of exhibition halls at the American Museum of Natural History on the Upper West Side in Manhattan, New York City. The halls opened on June 12, 2021, as a complete redesign of their predecessors, the Harry Frank Guggenheim Hall of Gems and Minerals and Morgan Memorial Hall of Gems. The halls feature thousands of rare gems, mineral specimens and pieces of jewelry.
Aquamarine is a pale-blue to light-green variety of beryl. The color of aquamarine can be changed by heat.
