We can find krypton in Nature almost exclusively as constituent gas of the atmosphere, where it is present in a concentration in the order of 0,00011% for volume of dry air. It is also present in small concentrations in some natural gases and in gases that emanate from thermal waters and from the volcanoes. It is the second rarer element in the terrestrial crust (considering oceans and atmosphere), where it is present in concentrations similar to those of xenon.