Cognomen เพชรรุจิ (เพชรรุจิ 
, Petchruji ) , all around the world, is an extremely rare surname. The cognomen เพชรรุจิ is habitual in South-eastern Asia, particularly Thailand, where it is an extremely rare surname. Much less frequently, เพชรรุจิ is the forename as well as the last name.