Argon is found in the Earth's atmosphere; it is also present in some potassium minerals due to the radioactive decay of isotope potassium-40. It is not found in compounds.
Argon belongs to the noble gases in the periodic table of elements. It is the third noble gas and is colorless and odorless in gas and liquid forms. It has the same solubility as oxygen. In the laboratory, argon is isolated from the fractional distillation of liquid air. Its uses include serving as an inert shielding gas in the welding industry and with incandescent fluorescent lighting. Argon is commonly known for the blue-green laser light it produces.