This pattern is so old that it can be found on Shosoin treasures from the Nara period (710-794) and is hexagonal in shape, derived from the shell of the tortoise, a symbol of longevity. A series of this pattern represents eternal prosperity.
Legend has it that when the phoenix appears, the reign of the emperor will be peaceful, and the paulownia tree, where the phoenix lives, was considered a noble tree and was even reserved exclusively for the imperial family. Later, even after it became popular among the general public, it remained popular as a lucky pattern signifying classy.