The term is "minerals." Few elements are found in their pure elemental form, and they are mostly metals.
Atomic weight or gram-atomic mass.
Phytosterols
Lead is an element---Go to http://en.wikipedia.org/ and look up lead---Natural or Synthetic is irrelevant when you're talking about elements. (If you don't know what I'm talking about, then maybe you ought to also read the wikipedia article on Chemical Element.)
The weighted average of all of the natural occuring isotopes for a particular element is called its Atomic Weight (or Relative Atomic Mass)
the noble gases
Synthetic
3 quarters of the 90 naturally occurring elements are called metals.
Almost all inorganic compounds contain metals, depending upon the type of bonding. These are mainly of 2 types: salts and complexes. Mostly alkali and alkaline earth metals form salts while transition metals form complexes.
Atomic weight, if the average is taken by weighting the mass of each naturally occurring isotope by its natural abundance.
Elements are composed of only one type of atom. There are about 90 or so naturally occurring elements.
... atomic mass or atomic weight.
This is the atomic weight of the element.
Atomic weight or gram-atomic mass.
Air contains naturally occurring chemicals called hydroxyl radicals that react with, and destroy, a range of pollutants and natural compounds
a naturally occurring solid mixture of minerals or organic matter is called
Phytosterols
The hardest naturally occurring substance is called diamond. It is a form of carbon.