National Museum of Natural HistoryThe National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. It has free admission and is open 364 days a year. In 2022, with 3.9 million visitors, it was the most-visited museum in the United States. Opened in 1910, the museum on the National Mall was one of the first Smithsonian buildings constructed exclusively to hold the national collections and research facilities.
Verneuil methodThe Verneuil method (or Verneuil process or Verneuil technique), also called flame fusion, was the first commercially successful method of manufacturing synthetic gemstones, developed in the late 1883 by the French chemist Auguste Verneuil. It is primarily used to produce the ruby, sapphire and padparadscha varieties of corundum, as well as the diamond simulants rutile, strontium titanate and spinel. The principle of the process involves melting a finely powdered substance using an oxyhydrogen flame, and crystallising the melted droplets into a boule.
Hope DiamondThe Hope Diamond is a diamond 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. The stone is one of the Golconda diamonds. The earliest records of the diamond show that French gem merchant Jean-Baptiste Tavernier purchased it in 1666 as the Tavernier Blue. The stone was cut and renamed the French Blue (Le bleu de France); Tavernier sold the stone to King Louis XIV of France in 1668.
LapidaryLapidary (from the Latin lapidarius) is the practice of shaping stone, minerals, or gemstones into decorative items such as cabochons, engraved gems (including cameos), and faceted designs. A person who practices lapidary is known as a lapidarist. A lapidarist uses the lapidary techniques of cutting, grinding, and polishing. Hardstone carving requires specialized carving techniques.
Placer depositIn geology, a placer deposit or placer is an accumulation of valuable minerals formed by gravity separation from a specific source rock during sedimentary processes. The name is from the Spanish word placer, meaning "alluvial sand". Placer mining is an important source of gold, and was the main technique used in the early years of many gold rushes, including the California Gold Rush. Types of placer deposits include alluvium, eluvium, beach placers, aeolian placers and paleo-placers.
BroochA brooch (ˈbroʊtʃ, also USˈbruːtʃ) is a decorative jewelry item designed to be attached to garments, often to fasten them together. It is usually made of metal, often silver or gold or some other material. Brooches are frequently decorated with enamel or with gemstones and may be solely for ornament or serve a practical function as a clothes fastener. The earliest known brooches are from the Bronze Age. As fashions in brooches changed rather quickly, they are important chronological indicators.
Czochralski methodThe Czochralski method, also Czochralski technique or Czochralski process, is a method of crystal growth used to obtain single crystals of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The method is named after Polish scientist Jan Czochralski, who invented the method in 1915 while investigating the crystallization rates of metals.
Diamond simulantA diamond simulant, diamond imitation or imitation diamond is an object or material with gemological characteristics similar to those of a diamond. Simulants are distinct from synthetic diamonds, which are actual diamonds exhibiting the same material properties as natural diamonds. Enhanced diamonds are also excluded from this definition. A diamond simulant may be artificial, natural, or in some cases a combination thereof.