Cerium
One of the properties of pure cerium is that it will ignite when it's scratched with a sharp object. It's present in the ‘flint’ of this lighter in a safer form as a component of 'misch metal'.
Large deposits of cerium is processed from ore deposits in mozanite on the beaches of Travancore in India, and river sands in Brazil as well as in allanite in the Western United States and in China, where a company called Jiangxi Metals Co., Ltd in Shanghai supplies quantities internationally for use in lighters as well as ‘boy scout’ camping flints.
