Seal Customs Terracotta Horse

This is what's called a Jian Ding (Certified) Export Approval Seals. They have been issued from around 1949 and are still being used on items that predate 1949 for export out of China. The seal does guarantee anything and items with it are rarely even 100 years old. for more detailed information here is a very good link https://gotheborg.com/marks/jiandingtest.shtml