Lucky Charm Specialist: Nachikuro Stone Frogs, Set of 2 Nachikuro Stone Nachikuro stone is a valuable natural stone that can only be found in a special place in Mie Prefecture. Frogs It seems that frogs have been considered lucky charms since ancient times. The wordplay with "frog (kaeru)" is very auspicious, such as "to return safely (buji ni kaeru)", "good fortune returns (fuku kaeru)", "money returns (okane ga kaeru)", and "to rejuvenate (wakagaeru)". Furthermore, the frog's leap forward is associated with improved career luck. Also, because they lay many eggs, they are also associated with good fortune in having children. When you line them up like this, "frog" is a specialist in lucky charms that can correspond to everything.