The average concentrations of protactinium in the Earth's crust is typically on the order of a few parts per trillion, but may reach up to a few parts per million in some uraninite ore deposits.
Konsentrasi protaktinium ring kerak gumi ketah nyané makudang wagian per triliun, sakéwanten prasida nganti makudang paham per yuta ring makidang endapan wijih uraninit.