Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Tarnish
open-in-new
<h2 id="chemistry">Chemistry</h2> <p>Tarnish is a product of a <a href="/facts/Chemical_reaction/GpqWlKrz">chemical reaction</a> between a <a href="/facts/Metal/PT8hNX6R">metal</a> and a <a href="/facts/Nonmetal_(chemistry)/0oejKuzK">nonmetal</a> <a href="/facts/Chemical_compound/37FXqqtv">compound</a>, especially <a href="/facts/Oxygen/acyn6o8r">oxygen</a> and <a href="/facts/Sulfur_dioxide/jDK1fIDs">sulfur dioxide</a>. It is usually a metal <a href="/facts/Oxide/DXtoVe1C">oxide</a>, the product of <a href="/facts/Oxidation/Pyd5RVcj">oxidation</a>; sometimes it is a metal sulfide. The metal oxide sometimes reacts with water to make the hydroxide, or with carbon dioxide to make the carbonate. It is a chemical change. There are various methods to prevent metals from tarnishing. </p> <h2 id="prevention-and-removal">Prevention and removal</h2> <p>Heavy tarnish can be mechanically removed by using tools such as a <a href="/facts/File_(tool)/jgKJ9cot">file</a> or abrasive materials such as <a href="/facts/Steel_wool/bb1r4qCG">steel wool</a>, <a href="/facts/Sandpaper/tWd80gSw">sandpaper</a>, <a href="/facts/Emery_paper/w22UoFDj">emery paper</a>, and heavy <a href="/facts/Polishing/SqMg0yh9">polishing</a> compounds. Lighter tarnish may be abrasively removed with lighter polishing compounds or chemicals such as <a href="/facts/Sodium_bicarbonate/S9oSol0R">baking soda</a>. Gentler abrasives, such as <a href="/facts/Calcium_carbonate/UQ1wLFna">calcium carbonate</a>, are often used by museums to clean tarnished <a href="/facts/Silver/xXe41BGg">silver</a>, which will not scratch it or leave unwanted residues.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a> Objects such as silverware may have their tarnish non-destructively reversed electrochemically by resting them on a piece of aluminium foil in a pot of boiling water with a small amount of salt or baking soda.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a><a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Revie, R. Winston; Uhlig, Herbert Henry (2008). Corrosion and corrosion control: an introduction to corrosion science and engineering (4th ed.). Hoboken, N.J: Wiley-Interscience. ISBN 978-0-471-73279-2. <a href="978-0-471-73279-2" target="_blank">978-0-471-73279-2</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"Guide to Tarnish". Rio Grande. 2019-08-14. Retrieved 2024-08-17. <a href="https://www.riogrande.com/knowledge-hub/guide-to-tarnish/" target="_blank">https://www.riogrande.com/knowledge-hub/guide-to-tarnish/</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>"Guide to Tarnish". Rio Grande. 2019-08-14. Retrieved 2024-08-17. <a href="https://www.riogrande.com/knowledge-hub/guide-to-tarnish/" target="_blank">https://www.riogrande.com/knowledge-hub/guide-to-tarnish/</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"Making it Shine". ohiohistory.wordpress.com. Ohio Historical Society. 2011-06-02. Archived from the original on 2012-03-23. Retrieved 2012-10-19. <a href="https://web.archive.org/web/20120323201653/http://ohiohistory.wordpress.com/2011/06/02/making-it-shine/" target="_blank">https://web.archive.org/web/20120323201653/http://ohiohistory.wordpress.com/2011/06/02/making-it-shine/</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"Finishing techniques in Metalwork". philamuseum.org. Philadelphia Museum of Art. Archived from the original on 2016-03-31. <a href="https://web.archive.org/web/20160331180638/http://www.philamuseum.org/booklets/7_44_85_1.html?page=2" target="_blank">https://web.archive.org/web/20160331180638/http://www.philamuseum.org/booklets/7_44_85_1.html?page=2</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Remove Tarnish from Silver". scifun.chem.wisc.edu. Department of Chemistry, University of Wisconsin-Madison. Archived from the original on 2018-04-01. Retrieved 2012-10-19. <a href="https://web.archive.org/web/20180401064415/http://scifun.chem.wisc.edu/homeexpts/TARNISH.html" target="_blank">https://web.archive.org/web/20180401064415/http://scifun.chem.wisc.edu/homeexpts/TARNISH.html</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> </ol>