Which two transuranium elements occur naturally in trace amounts?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — transuranium element Modern version of the periodic table of the elements (printable).

The two transuranium elements that occur in nature in trace amounts are neptunium and plutonium.1

While most transuranium elements are synthetic and produced through nuclear reactions, these two have been identified in trace quantities in natural environments. Because all transuranium elements are unstable and undergo radioactive decay, their existence in nature is limited, and they are primarily studied through laboratory synthesis.12