The assembly had long used 18-karat gold for its official member badges, but costs have surged in recent years. According to the assembly, the price of a single badge rose from 32,400 yen in fiscal 2018 to 66,000 yen by fiscal 2022.

With the next assembly election scheduled for two years from now, estimates for purchasing new badges in the upcoming fiscal year—including spares and those for former members—put the total cost at more than 30 million yen.

Faced with this sharp increase, the assembly’s steering committee voted to switch the badge material from solid gold to gold plating. Additionally, they decided to abolish badges for former members.

This change is expected to significantly reduce costs, slashing the total from around 30 million yen to about 2 million yen.
https://newsonjapan.com/article/147279.php