Gold can also be counterfeited.
https://coinweek.com/bullion-report/counterfeit-gold-silver-beware-fake-pamp-suisse-gold-bars/
https://veldtgold.com/fake-pamp-gold-bars/
https://www.fakebullion.com/index.php/news-updates/fakebullion-com-blog/61-improved-counterfeit-pamp-suisse-bars-on-the-way
http://www.bullionbaron.com/2014/08/replica-vs-real-1oz-gold-pamp-bar.html