Although there are elements we have not yet created or found in nature, scientists already know what they will be and can predict their properties. For example, element 125 has not been observed, but when it is, it will appear in a new row of the periodic table as a transition metal.

What elements are still undiscovered?

The last naturally occurring element to be discovered was francium (87) in 1939. Since that discovery, plutonium (94), neptunium (93) and astatine (85), which were initially created in the lab in 1940, have since been found in nature.

Could there be elements not found on Earth?

But when we look at the full gamut of elements in the periodic table, there's one missing that you might have expected to be there: the 43rd one, Technetium, a shiny, gray metal as dense as lead with a melting point of over 3,000 °F, that simply doesn't occur naturally on our world.