In one French Candlemas superstition, a Louis d'or may be held while flipping a crêpe.
The custom is associated with La Chandeleur, or Candlemas, celebrated in France on February 2. In the version described in reference accounts, the cook holds a gold coin—or sometimes a ring—in the left hand while flipping the crêpe with the right. A successful flip is said to promise wealth or good fortune in the coming year.
A Louis d'or was a French gold coin first introduced under Louis XIII in 1640. Its name means “Louis of gold” and refers to the king’s portrait on the coin. It was not a single fixed design: several denominations and later issues existed before the French franc replaced it during the revolutionary period.
The superstition is not a recipe requirement, and variations exist. Some versions place a gold coin on the crêpe, hide the first crêpe in a drawer, or associate the ritual with good weather rather than money. The key detail in this question is the named gold coin: the Louis d'or.