Editing Hope Diamond (section)

==Physical properties==
*'''Weight''': In December 1988, the [[Gemological Institute of America]]'s laboratory determined the diamond to weigh {{convert|45.52|carat|g oz}}.<ref name="twsI44fof" />
* '''Size and shape''': The diamond has been compared in size and shape to a pigeon egg<ref name=twsI35/> or a [[walnut]]<ref name=twsI41/><ref name=twsI44bb/> that is pear-shaped.<ref name=twsI44bb/> The length, width, and depth are 25.60&nbsp;mm × 21.78&nbsp;mm × 12.00&nbsp;mm (1&nbsp;in × 7/8&nbsp;in × 15/32&nbsp;in).<ref name=twsI44fof/>
* '''Color''': It has been described as being a "fancy dark greyish-blue"<ref name=twsI44fof/> as well as "dark blue in color,"<ref name=twsI44bb/> or having a "steely-blue" color.<ref name=twsI44ll/> [[Blue diamonds]] similar to the Hope can be shown by [[Tristimulus colorimeter|colorimetric]] measurements to be grayer (lower in [[saturation (color theory)|saturation]]) than blue sapphires.<ref>Hofer, Stephen, ''Collecting and Classifying Colored Diamonds'', p. 414 {{ISBN?}}</ref> In 1996, the Gemological Institute of America examined the diamond and, using their proprietary scale, graded it ''fancy deep grayish blue''.[[File:Hope Diamond Closeup.jpg|thumb|alt=Hope Diamond in the National Museum of Natural History, Washington DC.|The Hope Diamond in the National Museum of Natural History, Washington D.C., 2014.]]<ref>King, et al., "[https://archive.today/20120709173352/http://gia.metapress.com/content/q0n20t64308783g1/?p=c8bfbd0054ca46439c66bbd5f3ccceb3&pi=1 Characterizing Natural-color Type IIb Blue Diamonds]", ''[[Gems & Gemology]]'', Vol. 34, #01, p. 249</ref> Visually, the gray modifier (mask) is so dark (indigo) that it produces an "inky" effect, appearing almost blackish-blue in [[incandescent light]].<ref name="Wise" /> Current photographs of the Hope Diamond use high-intensity light sources that tend to maximize the brilliance of gemstones.<ref>Wise, ibid. pp. 29–30</ref> In popular literature, many superlatives have been used to describe the Hope Diamond as a "superfine deep blue," often comparing it to the color of a fine [[sapphire]]—for example, "blue of the most beautiful blue sapphire" (Deulafait)—and describing its color as "a sapphire blue."<ref name="Wise">Wise, Richard W., ''Secrets of the Gem Trade, The Connoisseur's Guide to Precious Gemstones'', Ch. 38, p. 235. {{ISBN|0-9728223-8-0}}.</ref><ref name="twsI44jj">{{Cite news |date=May 6, 1908 |title=Hope Diamond Is Sold; Sultan Said to Have Paid $400,000 for Famous Gem |work=The New York Times |url=https://query.nytimes.com/gst/abstract.html?res=F00D10FA3F5A17738DDDAF0894DD405B888CF1D3 |access-date=July 9, 2011 |quote=The stone is a sapphire blue diamond weighing 44 3/8 carats...}}</ref><ref>Note: Other references include Mawe (1823), Ball (1835), Bruton (1978), Tolansky (1962). However, these descriptions are somewhat wide of the mark.</ref> Tavernier described it as a "beautiful violet".<ref name="twsI44fof" />
* '''Phosphorescence''': The stone exhibits an unusually intense, brilliant red [[phosphorescence]] after exposure to short-wave ultraviolet light. This 'glow-in-the-dark' effect persists for some time after the light source has been switched off, and this strange quality may have helped fuel its reputation of being "cursed."<ref name=twsI35/> The red glow is a phenomenon of blue diamonds that helps scientists "fingerprint" them, allowing them to distinguish real ones from artificial ones.<ref name=twsI44hh/> The red glow occurs because of a mix of [[boron]] and [[nitrogen]] in the stone.<ref name="twsI44hh">{{Cite news |last=Randolph E. Schmid, Associated Press |date=January 8, 2008 |title=Blue diamonds have a red glow about them |work=USA Today |url=https://www.usatoday.com/tech/science/discoveries/2008-01-08-hope-diamond-glow_N.htm |access-date=July 9, 2011}}</ref>
* '''Clarity''': The clarity was determined to be VS1, with whitish graining present.<ref name=twsI44fof/>
* '''Cut''': The cut was described as being "cushion antique brilliant with a faceted girdle and extra facets on the pavilion."<ref name=twsI44fof/>
* '''Chemical composition''': In 2010, the diamond was removed from its setting to measure its [[chemical formula|chemical composition]]. After boring a hole one [[nanometer]] deep, preliminary experiments detected the presence of [[boron]], [[hydrogen]], and possibly [[nitrogen]]; the boron concentration varies from zero to eight parts per million.<ref>{{Cite magazine |last=Caputo |first=Joseph |date=November 2010 |title=Testing the Hope Diamond |url=http://www.smithsonianmag.com/science-nature/Testing-the-Hope-Diamond.html |url-status=dead |magazine=[[Smithsonian (magazine)|Smithsonian]] |archive-url=https://web.archive.org/web/20110113061200/http://www.smithsonianmag.com/science-nature/Testing-the-Hope-Diamond.html |archive-date=January 13, 2011 |access-date=January 15, 2011}}</ref> The boron is responsible for causing the blue color of the stone.<ref name=twsI44ee/>
* '''Touch and feel''': When [[Associated Press]] reporter [[Ron Edmonds]] was allowed by Smithsonian officials to hold the gem in his hands in 2003, he wrote that the first thought that had come into his mind was, "Wow!"<ref name="twsI44ee">{{Cite news |date=October 3, 2003 |title=Hope Diamond still holds allure |work=USA Today |agency=Associated Press |url=https://www.usatoday.com/news/science/2003-10-03-hope-diamond_x.htm |access-date=July 9, 2011 |quote=The Hope Diamond, center, is tested at the Smithsonian's Natural History Museum in Washington to try to determine what impurities give it its blue colors. ... By Ron Edmonds, AP ...}}</ref> It was described as "cool to the touch."<ref name=twsI44ee/> He wrote:
{{blockquote|You cradle the 45.5-carat stone—about the size of a walnut and heavier than its translucence makes it appear—turning it from side to side as the light flashes from its facets, knowing it's the hardest natural material yet fearful of dropping it.|[[Associated Press]] reporter Ron Edmonds in 2003<ref name=twsI44ee/>}}
* '''Hardness''': Diamonds in general, including the Hope Diamond, are the hardest natural minerals known on [[Earth]], but, because of weak planes in the bonds of a diamond's crystalline structure, the crystal can fracture along these planes if not handled correctly. These weak planes allow diamond cutters to split a rough uncut stone into smaller flawless parts before the process of faceting the stone takes place. Only a diamond can scratch another diamond, so, to create a faceted diamond, the uncut rough is mounted in a holder, and then the flat surfaces or facets are ground into the surface of the stone using specially made metal wheels impregnated with diamond particles. These facets are ground and polished using ever finer grades/grits of diamond powder until they have a clear mirror surface, ultimately producing a gem that sparkles by refracting and reflecting light in different ways.<ref name="twsOctU777">{{Cite news |last=Bergeron |first=Louis |date=2011-10-17 |title=Amorphous diamond, a new super-hard form of carbon created under ultrahigh pressure |language=en |work=[[Science Daily]] |url=https://www.sciencedaily.com/releases/2011/10/111017155714.htm |url-status=live |access-date=2011-10-21 |archive-url=https://web.archive.org/web/20230203142943/http://www.sciencedaily.com/releases/2011/10/111017155714.htm |archive-date=2023-02-03}}</ref>