Editing Gold (section)

=== Electronics ===
Only 10% of the world consumption of new gold produced goes to industry,<ref name="Soos-2011" /> but by far the most important industrial use for new gold is in fabrication of corrosion-free [[electrical connectors]] in computers and other electrical devices. For example, according to the World Gold Council, a typical cell phone may contain 50&nbsp;mg of gold, worth about three dollars. But since nearly one billion cell phones are produced each year, a gold value of US$2.82 in each phone adds to US$2.82 billion in gold from just this application.<ref>[http://www.usfunds.com/slideshows/the-many-uses-of-gold/ Uses of gold] {{Webarchive|url=https://archive.today/20141104233515/http://www.usfunds.com/slideshows/the-many-uses-of-gold/ |date=4 November 2014 }} Accessed 4 November 2014</ref> (Prices updated to November 2022)

Though gold is attacked by free chlorine, its good conductivity and general resistance to oxidation and corrosion in other environments (including resistance to non-chlorinated acids) has led to its widespread industrial use in the electronic era as a thin-layer coating on [[electrical connector]]s, thereby ensuring good connection. For example, gold is used in the connectors of the more expensive electronics cables, such as audio, video and [[USB]] cables. The benefit of using gold over other connector metals such as [[tin]] in these applications has been debated; gold connectors are often criticized by audio-visual experts as unnecessary for most consumers and seen as simply a marketing ploy. However, the use of gold in other applications in electronic sliding contacts in highly humid or corrosive atmospheres, and in use for contacts with a very high failure cost (certain [[computer]]s, communications equipment, [[spacecraft]], [[jet aircraft]] engines) remains very common.<ref>{{cite book |editor-last=Krech III |editor-first=Shepard |editor2-last=Merchant |editor2-first=Carolyn |editor3-last=McNeill |editor3-first=John Robert |title=Encyclopedia of World Environmental History |volume=2: F–N |year=2004 |publisher=Routledge |isbn=978-0-415-93734-4 |pages=597– |url={{google books |plainurl=y |id=G7JrhAy5phoC |page=597}} }}</ref>

Besides sliding electrical contacts, gold is also used in [[electrical contacts]] because of its resistance to [[corrosion]], [[electrical conductivity]], [[ductile|ductility]] and lack of [[toxicity]].<ref>{{cite web |title=General Electric Contact Materials |website=Electrical Contact Catalog (Material Catalog) |publisher=Tanaka Precious Metals |date=2005 |url=http://www.tanaka-precious.com/catalog/material.html|archive-url=https://web.archive.org/web/20010303213152/http://www.tanaka-precious.com/catalog/material.html|url-status=dead|archive-date=3 March 2001 |access-date=21 February 2007}}</ref> Switch contacts are generally subjected to more intense corrosion stress than are sliding contacts. Fine gold wires are used to connect [[semiconductor device]]s to their packages through a process known as [[wire bonding]].

The concentration of free electrons in gold metal is 5.91×10<sup>22</sup>&nbsp;cm<sup>−3</sup>.<ref>{{Cite book |url=https://books.google.com/books?id=MaWKDQAAQBAJ&pg=SA2-PA8 |title=Electronic, Magnetic, and Optical Materials, Second Edition |last1=Fulay |first1=Pradeep |last2=Lee |first2=Jung-Kun |date=2016 |publisher=CRC Press |isbn=978-1-4987-0173-0}}</ref> Gold is highly [[electrical conductivity|conductive]] to electricity and has been used for [[electrical wiring]] in some high-energy applications (only silver and copper are more conductive per volume, but gold has the advantage of corrosion resistance). For example, gold electrical wires were used during some of the [[Manhattan Project]]'s atomic experiments, but large high-current silver wires were used in the [[calutron]] isotope separator magnets in the project.

It is estimated that 16% of the world's presently-accounted-for gold and 22% of the world's silver is contained in electronic technology in Japan.<ref>{{cite news |url=http://www.techradar.com/news/phone-and-communications/mobile-phones/japan-wants-citizens-to-donate-their-phone-to-make-2020-olympic-medals-1326938 |title=Japan wants citizens to donate their old phone to make 2020 Olympics medals |work=TechRadar |date=23 August 2016 |author=Peckham, James}}</ref>