Editing Gemstone (section)

==Value==
[[File: Spanish jewellery-Gold and emerald pendant at VAM-01.jpg|thumb|upright|Spanish emerald and gold pendant at [[Victoria and Albert Museum]]]]
[[File:Pendant (cropped).jpg|thumb|upright|Enamelled gold, amethyst, and pearl pendant, about 1880, Pasquale Novissimo (1844–1914), V&A Museum number M.36-1928]]
Gemstones have no universally accepted grading system. Diamonds are graded using a system developed by the [[Gemological Institute of America]] (GIA) in the early 1950s. Historically, all gemstones were graded using the naked eye. The GIA system included a major innovation: the introduction of 10x magnification as the standard for grading clarity. Other gemstones are still graded using the naked eye (assuming 20/20 vision).<ref>Wise, R. W., 2006, ''Secrets of The Gem Trade, The Connoisseur's Guide to Precious Gemstones'', Brunswick House Press, p.36 {{ISBN| 0-9728223-8-0}}</ref>

A [[mnemonic device]], the "four Cs" (color, cut, clarity, and carats), has been introduced to help describe the factors used to grade a diamond. With modification, these categories can be useful in understanding the grading of all gemstones. The four criteria carry different weights depending upon whether they are applied to colored gemstones or to colorless diamonds. In diamonds, the cut is the primary determinant of value, followed by clarity and color. An ideally cut diamond will sparkle, to break down light into its constituent rainbow colors (dispersion), chop it up into bright little pieces (scintillation), and deliver it to the eye (brilliance). In its rough crystalline form, a diamond will do none of these things; it requires proper fashioning and this is called "cut". In gemstones that have color, including colored diamonds, the purity, and beauty of that color is the primary determinant of quality.<ref>Wise, R. W., 2006, ''Secrets of The Gem Trade, The Connoisseur's Guide to Precious Gemstones'', Brunswick House Press, p. 15</ref>

Physical characteristics that make a colored stone valuable are color, clarity to a lesser extent (emeralds will always have a number of inclusions), cut, unusual [[optical phenomena]] within the stone such as color zoning (the uneven distribution of coloring within a gem)<ref>{{Cite web |title=Zoning (Colour Banding) |url=https://www.gemporia.com/en-gb/learning-library/terms/zoning%20(colour%20banding)/ |access-date=2024-03-01 |website=www.gemporia.com |language=en-GB}}</ref> and [[star stone|asteria]] (star effects).

Apart from the more generic and commonly used gemstones such as  from [[diamond]]s, [[Ruby|rubies]], [[sapphire]]s, and [[emerald]]s, [[pearl]]s and [[opal]]<ref name=church>{{cite book | last = Church | first = A.H. | title = Precious Stones considered in their scientific and artistic relations | publisher = His Majesty's Stationery Office, Wyman & Sons | date = 1905|page = 11|chapter = Definition of Precious Stones |url = http://www.farlang.com/gemstones/church-precious-stones/page_011 |archive-url= https://web.archive.org/web/20070929092547/http://www.farlang.com/gemstones/church-precious-stones/page_011 |archive-date= 2007-09-29 | via = Farlang.com}}</ref> have also been defined as precious in the jewellery trade. Up to the discoveries of bulk [[amethyst]] in Brazil in the 19th century, amethyst was considered a "precious stone" as well, going back to ancient Greece. Even in the last century certain stones such as [[Aquamarines|aquamarine]], [[peridot]] and cat's eye ([[cymophane]]) have been popular and hence been regarded as precious, thus reinforcing the notion that a mineral's rarity may have been implicated in its classification as a precious stone and thus contribute to its value.

Today the gemstone trade no longer makes such a distinction.<ref name="WiseSecrets1" /> Many gemstones are used in even the most expensive jewelry, depending on the brand-name of the designer, fashion trends, market supply, treatments, etc. Nevertheless, diamonds, rubies, sapphires, and emeralds still have a reputation that exceeds those of other gemstones.<ref>{{cite web |website = HowStuffWorks.com |url= http://adventure.howstuffworks.com/outdoor-activities/climbing/5-most-precious-stones.htm |title= 5 Most Precious Stones |url-status= live |archive-url= https://web.archive.org/web/20141106143228/http://adventure.howstuffworks.com/outdoor-activities/climbing/5-most-precious-stones.htm |archive-date= 2014-11-06 |date= 2009-11-09 }}</ref>

Rare or unusual gemstones, generally understood to include those gemstones which occur so infrequently in gem quality that they are scarcely known except to connoisseurs, include [[andalusite]], [[axinite]], [[cassiterite]], [[clinohumite]], [[painite]] and [[red beryl]].<ref>{{Cite news |url= http://www.jewellerymonthly.com/what-is-a-gemstone/|title= A complete guide to Gemstones|date= 2015-04-02 |work= Jewellery Monthly|language= en-GB|url-status= live|archive-url= https://web.archive.org/web/20170828191332/http://www.jewellerymonthly.com/what-is-a-gemstone/|archive-date= 2017-08-28}}</ref>

Gemstone pricing and value are governed by factors and characteristics in the quality of the stone. These characteristics include clarity, rarity, freedom from defects, the beauty of the stone, as well as the demand for such stones. There are different pricing influencers for both colored gemstones, and for diamonds. The pricing on colored stones is determined by market supply-and-demand, but diamonds are more intricate.<ref>{{Cite web|title=Pricing of Colored Gemstones {{!}} Joseph Menzie Inc|url=https://menzie.com/colored-gemstone-sales/prices-for-gemstones/|access-date=2021-10-27|language=en-US|archive-date=October 27, 2021|archive-url=https://web.archive.org/web/20211027172652/https://menzie.com/colored-gemstone-sales/prices-for-gemstones/|url-status=live}}</ref>

In the addition to the aesthetic and adorning/ornamental purpose of gemstones, there are many proponents of [[energy medicine]] who also value gemstones on the basis of their alleged [[healing]] powers.<ref>{{cite book |last1=Katz |first1=Michael |url=https://books.google.com/books?id=WUpDAAAACAAJ |title=Gemstone Energy Medicine: Healing Body, Mind and Spirit |date=2005 |publisher=Natural Healing Press |isbn=9780924700248 |access-date=2020-04-06}}</ref>

A gemstone that has been rising in popularity is Cuprian Elbaite Tourmaline which is also called "Paraiba Tourmaline". It was first discovered in the late 1980s in Paraíba, Brazil and later in Mozambique and Nigeria.<ref>{{cite web |url=https://www.gia.edu/gems-gemology/winter-2019-paraiba-tourmaline-geographic-origin-determination |title=Geographic Origin Determination of Paraíba Tourmaline |access-date=March 17, 2022 |archive-date=April 9, 2022 |archive-url=https://web.archive.org/web/20220409023403/https://www.gia.edu/gems-gemology/winter-2019-paraiba-tourmaline-geographic-origin-determination |url-status=live }}</ref> It is famous for its glowing neon blue color. Paraiba Tourmaline has become one of the most popular gemstones in recent times thanks to its color and is considered to be one of the important gemstones after rubies, emeralds, and sapphires according to Gübelin Gemlab. Even though it is a tourmaline, Paraiba Tourmaline is one of the most expensive gemstones.<ref>{{Cite web |title=International Gem Society LLC |work=International Gem Society |url=https://www.gemsociety.org/article/paraiba-tourmaline/}}</ref>