To Whom it may concern, This is a note of caution for the "scientificness" of this public outreach article. Helium-3 is not a mineral....it is an isotope of helium (there are 2, helium-3 and helium-4. The istopes are atoms of the same element that differ on the number of mass, which depends on the number of neutrons in the elements nucleus. So, helium 3 has two protons and one neutron, making a total of 3 particles in the nuclues-number of mass-, and helium 4 has 2 protons and 2 neutrons, a total of 4 particles in the nucleus). A mineral is a more complex structure, which involves several atoms (usually of different elements), with a specific crystallographic structure (ordered). You may look in chemical and geologic glossaries for further explanation. Best Regards, Vera Assis Fernandes