all commercial production of helium comes from natural gas. there are two basic types of commercial helium deposits: natural gas produced primarily for the hydrocarbon content, typically containing less than 3 percent helium; and gas with little or no hydrocarbons, produced solely for the helium, which typically makes up between 5 and 10 percent of the gas. although natural gas in which helium is only a byproduct contains a much lower percentage of helium, historically it has supplied the most helium.