What does 925 rj9 mean on a ring?

The marking "925" on a ring indicates that the metal is sterling silver, which is composed of 92.5% silver and 7.5% other metals, typically copper. The "RJ9" could be a manufacturer's or designer's mark, identifying the specific brand or creator of the piece. Together, these markings signify that the ring is made of high-quality sterling silver and can help in identifying its origin.