Travel Theme: Metal

I understand there are four categories of metal: Base metals, Ferrous metals, Noble metals, and Precious metals. And under these categories, there are 91 types of metal: 6 Alkali metals; 6 Alkaline earth metals; 38 Transition metals; 11 Post-transition metals; 15 Lanthanoids; and 15 Actinoids. I’m pretty sure that these photos represent one or more of these… 😉

Participate in this challenge here: http://wheresmybackpack.com/2014/05/23/metal/