The Periodic Table is comprised of metals and nonmetals. Most elements on the table are metals. Alkali metals represent a special group of elements on the periodical table as the Group 1 elements (excluding hydrogen). These metals are unique for several reasons:
1) shiny/silvery composition
2)extremely soft, can be cut with a knife
3)highly reactive, easily lose their +1 charge
When exposed to air, alkali metals' shiny exterior will tarnish due to oxidation.
All alkali metals can be found in nature. The list includes:lithium, potassium, sodium, rubidium, caesium, and francium.