In the Czech Republic, a carp scale is kept as a symbol of good luck.
The custom is especially associated with prosperity and money. After the traditional Christmas Eve carp meal, people may place one or more scales beneath a dinner plate, carry them in a wallet, or keep them elsewhere as an auspicious token for the coming year. Their coin-like shape helps explain the connection with wealth.
Christmas carp became established in Central European Christmas cuisine partly because fish was permitted during the Advent fast, when meat was restricted by Christian practice. In the Czech Republic, live carp are traditionally sold before Christmas, and some families temporarily keep the fish in a household bathtub before preparing it.
The scale is easy to confuse with other parts of the fish that appear in regional customs. Some traditions attach symbolism to the carp’s head or bones, but the Czech good-luck symbol specifically identified with wealth is the scale. The broader Christmas carp tradition is also found in Slovakia and other parts of Central Europe, though details vary by region.