The health conscious will know that potassium is good for the heart and you can get plenty by eating bananas. Not too many people know, or care, that potassium is a silvery metal. A good reason for this is that it only stays a metal in the vacuum of space or when surrounded by a noble gas. The slightest trace of oxygen - or most any other element for that matter - quickly reacts with it to form compounds.

Even under mineral oil, which is very inert, a piece of potassium will manage to tarnish from trace impurities. At least it's a beautiful purplish blue shade!

Note additional options for this element on the Ampules section

CAS 7440-21-3