I believe it is Uranium. All elements heavier than uranium are man-made.
Here's an interesting article...
http://space.newscientist.com/article/dn13828-has-the-heaviest-element-been-found.html
The heaviest element announced in February 2004 was ununpentium with the atomic number 115.
Sodium
Hydrogen has the lowest atomic number, and is not found in nature as individual atoms, but is found in nature as the diatomic molecule, H2.
Now californium is considered as the heaviest naturally occurring chemical element.
hydrogen
Mercury is the heaviest element at a liquid state.
The heaviest element announced in February 2004 was ununpentium with the atomic number 115.
its an element, so yes, any thing that's not manufactured by man is natural, therefore found in nature. It is not, however, found unless forced by man; so for most practical purposes it is not found in nature.
I think this is a trick question. The heaviest NATURAL element is Uranium (#92) but there are several heavier man-made ones. Every couple of years they are able to make another heavier one and IT becomes the heaviest. So I think the answer should be "there is no HEAVIEST element in the periodic table - it keeps changing."
If you are talking about element sin the periodic table, it is ununoctium(Uuo)
The heaviest element that is highly radioactive is Ununoctium, which has an atomic number of 118.
The heaviest element in the periodic table (known in March 2013) is ununoctium.
An element is an element, whether it is found in nature or created in a lab.
There are 88.
Roentgenium is an artificial element, not found in the nature.
Americium is an artificial element, don't exist in the nature.
The information in the question 'What is the heaviest element?' should answer this. Access this by the web link below.