A gemstone is a piece of mineral crystal which, when cut or polished, is used to make jewelry or other adornments. Certain rocks and occasionally organic materials that are not minerals may also be used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some softer minerals such as brazilianite may be used in jewelry because of their color or luster or other physical properties that have aesthetic value. However, generally speaking, soft minerals are not typically used as gemstones by virtue of their brittleness and lack of durability.
An engagement ring, also known as a betrothal ring, is a ring indicating that the person wearing it is engaged to be married, especially in Western cultures. A ring is presented as an engagement gift by a partner to their prospective spouse when they propose marriage to represent a formal agreement to future marriage. In most Western countries, engagement rings are usually worn only by women, and they are typically adorned with diamonds. In some countries, partners wear matching rings, and engagement rings may also be used as wedding rings. In the Anglosphere, the ring is customarily worn on the left hand ring finger, but customs vary across the world.
Diamond cutting is the practice of shaping a diamond from a rough stone into a faceted gem. Cutting diamonds requires specialized knowledge, tools, equipment, and techniques because of its extreme difficulty.
Tiffany & Co. is an American luxury jewelry and specialty design house headquartered on Fifth Avenue in Manhattan. Tiffany is known for its luxury goods, particularly its sterling silver and diamond jewelry. These goods are sold at Tiffany stores, online, and through corporate merchandising. Its name and branding are licensed to Coty for fragrances and to Luxottica for eyewear.
Van Cleef & Arpels is a French luxury jewelry company. It was founded in 1896 by the Dutch diamond-cutter Alfred Van Cleef and his father-in-law Salomon Arpels in Paris. Their pieces often feature flowers, animals, and fairies, and have been worn by style icons and royalty such as Grace Kelly, Jacqueline Kennedy Onassis, Diana, Princess of Wales, Ava Gardner, Farah Pahlavi, Eva Perón, Elizabeth Taylor, the Duchess of Windsor, Queen Nazli of Egypt, and Queen Camilla.
A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut refers to shape, and also the symmetry, proportioning and polish of a diamond. The cut of a diamond greatly affects a diamond's brilliance—a poorly-cut diamond is less luminous.
The Gemological Institute of America (GIA) is a nonprofit institute based in Carlsbad, California. It is dedicated to research and education in the field of gemology and the jewelry arts. Founded in 1931, GIA's mission is to protect buyers and sellers of gemstones by setting and maintaining the standards used to evaluate gemstone quality. The institute does so through research, gem identification, diamond grading services, and a variety of educational programs. Through its library and subject experts, GIA acts as a resource of gem and jewelry information for the trade, the public and media outlets.
Harry Winston was an American jeweler. He donated the Hope Diamond to the Smithsonian Institution in 1958 after owning it for a decade. He also traded the Portuguese Diamond to the Smithsonian in 1963 in exchange for 3,800 carats of small diamonds.
A trilliant cut, sometimes called a trillion, trillian, or Trielle is a triangular type of gemstone cut. The cut has many variations. It may have curved or uncurved sides. The shape of the top surface, or table, also varies.
A tension ring is a type of finger ring that holds a gemstone in place by pressure rather than prongs, a bezel or other mounting. The metal setting is actually spring-loaded to exert pressure onto the gemstone, and tiny etchings or grooves in the metal create a shelf that supports the gemstone's edges. The gemstone appears to be suspended in the air with nothing holding it in place.
Stonesetting is the art of securely setting or attaching gemstones into jewelry.
The Tiffany Yellow Diamond is one of the largest yellow diamonds ever discovered. Its carat weight was originally 287.42 carats in the rough when discovered in 1878 in the Kimberley mine in South Africa. It was cut into a cushion shape of 128.54 carats with 82 facets—24 more than a traditional round brilliant—to maximize its brilliance. The facet pattern features eight needle-like facets pointing outward from the culet (bottom) facet. Jewelry and diamond historian Herbert Tillander refers to this as a "stellar brilliant cut", and lists the gem in his book, Diamond Cuts in Historic Jewelry – 1381 to 1910 (1995), among other such diamonds: the Cullinan Diamond, the Koh-i-Noor, the Polar Star, the Wittelsbach, and others.
A bezel is a wider and usually thicker section of the hoop of a ring, which may contain a gem or a flat surface. Rings are normally worn to display bezels on the upper or outer side of the finger. In gem-cutting the term bezel is used for those sloping facets of a cut stone that surround the flat table face, which is the large, horizontal facet on the top.
Diamond is a gemstone formed by cutting a raw diamond. Diamonds are one of the best-known and most sought-after gems, and they have been used as decorative items since ancient times.
A birthstone is a gemstone that represents a person's birth period, usually the month or zodiac sign. Birthstones are often worn as jewelry or a pendant necklace.
Brown diamonds are the most common color variety of natural diamonds. In most mines, brown diamonds account for 15% of production. The brown color makes them less attractive to some people as gemstones, and most are used for industrial purposes. However, improved marketing programs, especially in Australia and the United States, have resulted in brown diamonds becoming valued as gemstones and even referred to as chocolate diamonds.
The Black Star of Queensland, also known as the Brimstone of Queensland, named after its nature and place of origin, is a 733-carat black sapphire, and was the world's largest gem quality star sapphire until The Star of Adam was discovered.
ImaGem Inc. is a gem information company based on patented technology for grading and identifying gems. The parent company, ImageStatistics, offers applications in imaging and image processing for the medical, pharmaceutical, manufacturing, chemical and quality assurance industries. ImaGem was created after 20 years of research done on human perception and ImageStatistics, a statistical tool developed by Dr. Lalit K. Aggarwal. ImaGem’s Systems employ advanced optics, imaging technology and proprietary software programs to automate and integrate diamond grading. In addition to evaluating the 4C’s of diamond grading, ImaGem also analyzes Light behavior information based on precise and repeatable measures; three complementary dimensions of brilliance, intensity and sparkle. ImaGem has created a system of uniquely identifying and registering (fingerprinting) a stone without any need for laser inscription. By offering all this information, ImaGem has promoted decision-making and efficiency in the gem industry supply chain. In 1998, ImaGem Inc. was incorporated in the state of Pennsylvania, USA after funding from a major retailer, Ben Franklin Technology Partnership, and private funding. The company has developed an integrated technology to collect image data for diamonds and gemstones, analyze it using direct measurement methodology and grade for precise and repeatable measurements.
Tacori is an American jewelry design house and manufacturer based in Glendale, California. The brand is heavily associated with bridal jewelry.
The Star of Burma is an 83-carat (16.6 g) cabochon-cut star ruby. In 1935, the Burmese ruby was purchased by Howard Hoeffer of jeweler Trabert & Hoeffer-Mauboussin, whereupon it was used in several Hollywood films in the 1930s, including the musical comedy Vogues of 1938. Trabert & Hoeffer-Mauboussin sold the jewel on September 14, 2004.
