Last name 古金 (古金 
, Gookin 
) , in the world, is a rare surname. The cognomen 古金 is characteristic of the United States, where it is a rare surname, Canada, where it is a very rare surname, and the United Kingdom, where it is an extremely rare surname. Measured by absolute frequency, it most frequently occurs in the United States, China, and Canada. Much less frequently, 古金 is the forename as well as the last name.