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.
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.
Tanzanite is the blue and violet variety of the mineral zoisite, caused by small amounts of vanadium. Tanzanite belongs to the epidote mineral group. Tanzanite is only found in Simanjiro District of Manyara Region in Tanzania, in a very small mining area approximately 7 km (4.3 mi) long and 2 km (1.2 mi) wide near the Mererani Hills.
A chemically pure and structurally perfect diamond is perfectly transparent with no hue, or color. However, in reality almost no gem-sized natural diamonds are absolutely perfect. The color of a diamond may be affected by chemical impurities and/or structural defects in the crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value. For example, most white diamonds are discounted in price when more yellow hue is detectable, while intense pink diamonds or blue diamonds can be dramatically more valuable. Of all colored diamonds, red diamonds are the rarest. The Aurora Pyramid of Hope displays a spectacular array of naturally colored diamonds, including red diamonds.
Demantoid is the green gemstone variety of the mineral andradite, a member of the garnet group of minerals. Andradite is a calcium- and iron-rich garnet. The chemical formula is Ca3Fe2(SiO4)3 with chromium substitution as the cause of the demantoid green color. Ferric iron is the cause of the yellow in the stone.
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.
Diamonds were largely inaccessible to investors until the recent advent of regulated commodities, due to a lack of price discovery and transparency. The characteristics of individual diamonds, especially the carat weight, color and clarity, have significant impact on values, but transactions were always private. With the standardized commodity as an underlying asset, several market traded financial instruments have been announced.
The Asian Institute of Gemological Sciences (AIGS) is a private gemological school and gemological laboratory based in Bangkok, Thailand.
Martin Rapaport is the chairman of the Rapaport Group and founder of the Rapaport Diamond Report and RapNet, an online diamond trading network. Known for his influential role in the diamond industry, Rapaport has been both a pioneer and a controversial figure, advocating for price transparency, ethical sourcing, and the commoditization of diamonds. His work extends beyond market analysis to include contributions to addressing conflict diamonds, promoting Fair Trade practices, and engaging with non-governmental organizations on industry ethics.
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.
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).
Richard W. Hughes is an American gemologist and author, known as an authority on corundum, rubies and sapphires.
WD Lab Grown Diamonds was a manufacturer of synthetic chemical vapor deposition (CVD) diamonds, headquartered in the Washington, D.C. area. Founded in 2008, WD produced lab-grown diamonds for distribution under the brands WD Lab Grown Diamonds and Latitude, in addition to creating diamonds for high-tech Advanced Materials applications. The company formally pivoted and relaunched as WD Advanced Materials, LLC in November 2023.
Worthy.com is an online liquidation marketplace for pre-owned luxury goods including diamonds, brand-named watches, and diamond jewelry. Worthy is headquartered in New York City and was founded by investment banker Ben De-Kalo in 2014.
Gem & Jewellery Export Promotion Council (GJEPC) is an organisation set up by the Government of India (GOI) with aim to promote the Indian gem and jewellery industry and its products.
Gemological Science International, or GSI, is an independent gemological organization that is one of the largest gemological entities in the world, with offices in four continents.
Larisa Popova is an Italian gemologist, appraiser and jeweler.
