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.
A pearl is a hard, glistening object produced within the soft tissue of a living shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pearl is composed of calcium carbonate in minute crystalline form, which has deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other shapes, known as baroque pearls, can occur. The finest quality of natural pearls have been highly valued as gemstones and objects of beauty for many centuries. Because of this, pearl has become a metaphor for something rare, fine, admirable and valuable.
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, cobalt, lead, chromium, vanadium, magnesium, boron, and silicon. The name sapphire is derived from the Latin word sapphirus, itself from the Greek word sappheiros (σάπφειρος), 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 the 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.
Ruby is a pinkish red to blood-red colored gemstone, a variety of the mineral corundum. Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapphires. Ruby is one of the traditional cardinal gems, alongside amethyst, sapphire, emerald, and diamond. The word ruby comes from ruber, Latin for red. The color of a ruby is due to the element chromium.
Gemology or gemmology is the science dealing with natural and artificial gemstone materials. It is a specific interdisciplinary branch of mineralogy. Some jewelers are academically trained gemologists and are qualified to identify and evaluate gems.
Crown jewels are the objects of metalwork and jewellery in the regalia of a current or former monarchy. They are often used for the coronation of a monarch and a few other ceremonial occasions. A monarch may often be shown wearing them in portraits, as they symbolize the power and continuity of the monarchy. Additions to them may be made, but, since medieval times, the existing items have been typically passed down unchanged, symbolizing the continuity of a monarchy.
The French Crown Jewels and Regalia comprise the crowns, orb, sceptres, diadems and jewels that were symbols of Royal or Imperial power between 752 and 1870. These were worn by many Kings and Queens of France as well as Emperor Napoleon. The set was finally broken up, with most of it sold off in 1885 by the Third Republic. The surviving French Crown Jewels, principally a set of historic crowns, diadems and parures, are mainly on display in the Galerie d'Apollon of the Louvre, France's premier museum and former royal palace, together with the Regent Diamond, the Sancy Diamond and the 105-carat (21.0 g) Côte-de-Bretagne red spinel, carved into the form of a dragon. In addition, some gemstones and jewels are on display in the Treasury vault of the Mineralogy gallery in the National Museum of Natural History.
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.
The American Gem Society (AGS) is a trade association of retail jewelers, independent appraisers, suppliers, and selective industry members, which was founded in 1934 by Robert M. Shipley.
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.
International Gemological Institute (IGI) is a Belgian diamond, colored stone and jewelry certification organization. Established in 1975, it is the largest independent gemological laboratory worldwide.
The Empress's Crown or Shahbanu’s Crown is part of the coronation regalia used by the third Shahbanu (Empress) of Iran (Persia), Farah Pahlavi. The crown is part of the Iranian National Jewels, and is currently on display at the Treasury of National Jewels in Tehran.
Richard T. Liddicoat, Jr. was an American gemologist. An educator in gemology, he contributed in the area of diamond quality grading and gem identification. Liddicoat was the Chairman of the Board of Governors at the Gemological Institute of America (GIA).
The so-called Muscovy Crown was a part of the Polish Crown Jewels. It was made in about 1610 in anticipation of Prince Władysław Vasa's coronation as Tsar of Russia, which was also known as Muscovy. Due to his father's opposition and a popular uprising in Russia, he never actually took the Russian throne, despite being elected by the Seven Boyars. Nevertheless, until 1634 he used the title of Grand Duke of Muscovy.
Regalia of the Russian tsars are the insignia of tsars and emperors of Russia, who ruled from the 13th to the 19th century. Over the centuries, the specific items used by Tsars changed greatly; the largest such shift occurred in the 18th century, when Peter the Great reformed the state to align it more closely with Western European monarchies.
Richard W. Hughes is an American gemologist and author, known as an authority on corundum, rubies and sapphires.
The Princie Diamond is an approximately 34.65-carat cushion-cut fancy intense pink diamond discovered 300 years ago in the Golconda mines. Christie's say that the Princie Diamond is believed to be the fourth largest pink diamond in the world, after the Daria-i-Noor, the Noor-ol-Ain - which are both part of the Iranian Crown Jewels; both were cut, according to experts, from one single c. 242-carat pink diamond, - and the Pink Star, a diamond weighing 59.60 carats.
The Georgian Crown Jewels were the regalia and vestments worn by the monarchs of Georgia during the coronation ceremony and at other state functions. The last Georgian monarchs, Heraclius II and George XII, had their regalia invested, respectively in 1783 and 1798, from the Russian tsars, their official protectors. Of these royal jewels—a crown, sword, and scepter—only the latter staff survives, in the collection of the Kremlin Armoury in Moscow.
Henry Ho is a jeweler in Thailand and President of the Bangkok Diamond & Precious Stones Exchange.
