Mithril
A durable silvery metal that is very light and easy to work, mined by Dwarves. From 'mith', grey, and 'ril', glitter. (Middle Earth)
Silver
A brilliant white metal, harder than gold. Used in jewelry, photography and electronics. (Anglo-Saxon, Seolfor: L. argentum: silver)
Gundanium
An almost immutable, heat-resistant, and electrically neutral material that can absorb Electro-magnetic waves. (Gundam)
Iodine
A bluish-black, lustrous solid that is a blue-violet gas. Found in seaweed and used in medicine. (Gr. iodes: violet)
Etherium
An extremely rare metal created by the sphinx Crucius the Mad. Vedalken wizards strive to infuse everything with etherium. (Magic: The Gathering)
Thanks for the link. Silver & iodine are real, but.....