This element is the lightest alkali metal and it is very reactive. This metal is used for the production of dry cells and storage batteries (for cell phones, car batteries, etc.). The carbonate of this metal is used for the treatment of some mental decease.
This element is a transition metal used in large amounts by the electrical industry in the form of wire. This metal is the second-best in the electrical conductance. Because this element resists corrosion in air, moisture and seawater, it has been widely used in coins.
This is a transition metal. This is a metal of the platinum family and it is the most corrosion-resistant metal known. It is used in the production of the alloys with osmium and platinum and in the production of crucibles and devices requiring high temperatures.