All elements heavier than plutonium are entirely synthetic; they are created in nuclear reactors or particle accelerators. The half lives of these elements show a general trend of decreasing as atomic numbers increase. ... The naming of transuranic elements may be a source of controversy.

Are all transuranium elements synthetic?

The elements following uranium on the periodic table are only produced artificially, and are known as the transuranium or transuranic elements. These elements may have existed on Earth early in its history, but like technetium, would have long ago decayed into more stable elements.

Are the transuranic elements all considered to be exclusively synthetic?

Plutonium and other so-called transuranic elements are considered by most to be man-made elements. ... This element has usually been considered synthetic because it is produced most efficiently in nuclear reactors.