Spark ionization (also known as spark source ionization) is a method used to produce gas phase ions from a solid sample. The prepared solid sample is vaporized and partially ionized by an intermittent discharge or spark.[1] This technique is primarily used in the field of mass spectrometry. When incorporated with a mass spectrometer the complete instrument is referred to as a spark ionization mass spectrometer or as a spark source mass spectrometer (SSMS).[2]