Just purchased a Korean coin.dont know if North or South or what the 4292 at the top means.How to find out?

Question

it also has a 100 on the side with 4292 and the words Republic of Korea.other side has picture of man and six characters-two large, four small

Answer 1

Its South Korean, a 1959 (thats 4292 on the Korean calendar system) 100 Hwan.  If its uncirculated, its worth $10-15.  If its been even lightly circulated its worth no more than $4.  Should weight 6.74 grams, 26 mm in diameter, made of copper-nickel.