<page_title> Nuclide </page_title> <section_title> Summary table for numbers of each class of nuclides </section_title> <table> <cell> 253 <col_header> Running total </col_header> </cell> <cell> Total of classically stable nuclides. <col_header> Notes on running total </col_header> </cell> <cell> Radioactive non-primordial, but naturally occurring on Earth. <col_header> Stability class </col_header> </cell> <cell> ~ 339 <col_header> Running total </col_header> </cell> </table>
253 stable nuclides exist on Earth, for a total of about 339 naturally occurring nuclides.