Boron-10 is a stable isotope of the element boron, which has an atomic number of 5. It contains 5 protons and 5 neutrons in its nucleus, making it one of the two naturally occurring isotopes of boron, the other being Boron-11. Boron-10 is less abundant, comprising about 19.9% of natural boron. This isotope is notable for its ability to capture neutrons, making it useful in various applications, including nuclear reactors and radiation shielding. Additionally, it is employed in medical treatments for certain types of cancer, particularly in boron neutron capture therapy (BNCT).