Indium: A very soft silvery-white metal with luster. Used in alloys for mirrors and in electronics. (Gr. indikon: indigo color)
Potassium: An abundant metal also known as ‘potash’. Essential for plant growth. (L. kalium, alkali).
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)