https://jeltsch.org/en/tags/sodium-hydroxide/Recent content in Sodium Hydroxide on Michael’s DomainHugoen-usCopyright © 2002 - 2026 Michael Jeltsch.Fri, 24 Jul 2026 00:18:18 +0300https://jeltsch.org/en/silver_and_gold_coating_a_5_cent_coin/Tue, 07 Mar 2017 00:00:00 +0000https://jeltsch.org/en/silver_and_gold_coating_a_5_cent_coin/<p>Last Friday, I coated with my kids 5 cent (copper) coins. They look pretty nice even though its only zinc and brass. All you need is a clean copper coin (you can clean old coins efficiently with vinegar), sodium hydroxide (NaOH), zinc powder and a hot plate. The original method (see this <a href="http://www.chymist.com/copper%20silver%20gold%20expl.pdf" target="_blank" rel="noopener noreferrer nofollow">PDF&nbsp; <svg class="svg-inline--fa fas fa-up-right-from-square fa-2xs" fill="currentColor" aria-hidden="true" role="img" viewBox="0 0 512 512" overflow="visible"><use href="#fas-up-right-from-square"></use></svg></a> ) uses a bunsen burner, but we did the heating and the final conversion of the zinc-plated coin into a brass-plated coin simply by placing it on our kitchen&rsquo;s hot plate. Hot sodium hydroxide is pretty dangerous, so be warned (eye protection) and keep the kids under control!</p>