21Ne

Neon (Ne) is a chemical element that exists as several stable isotopes. One of these isotopes is neon-21 (21Ne), which has a mass number of 21. It is a stable isotope, meaning it does not undergo radioactive decay. In natural neon, 21Ne is present in very low abundance, making up approximately 0.27% of the total neon on Earth. This makes it one of the rarer isotopes of neon, with the most abundant being 20Ne at about 90.48% and 22Ne at about 9.22%.

Neon-21 is produced in nature through several processes, including cosmic ray spallation of magnesium, which can be used as a tool in geology and cosmochemistry to study the exposure of rocks to cosmic rays and the history of planetary surfaces. Additionally, its presence can provide insights into the processes that have affected the materials in which it is found.

Due to its low natural abundance, 21Ne is not typically used in industrial applications. However, it may be of interest in scientific research, particularly in fields that study isotopic compositions and processes that produce or alter isotopes.