Production: Although Helium is one of the most common elements in the universe it is a rare gas on earth. It exists in the atmosphere in such
small quantities (less than five parts per million) that recovering it
from the air is uneconomical. Helium is produced as a by-product of the
refining of natural gas, which is carried out on a commercial scale in the
USA and Poland. In these areas natural gas contains a relatively high
concentration of Helium which has accumulated as a result of radioactive
decay of heavy elements within the earth's crust. …
