What does PJM mean stamped inside my 925 siver ring from China?

The "PJM" stamp inside your 925 silver ring likely indicates the manufacturer or designer of the jewelry, as it is common for jewelry pieces to carry initials or codes to identify their origin. The "925" mark signifies that the ring is made of sterling silver, which contains 92.5% silver and 7.5% other metals, typically copper. If you want more specific information about "PJM," you might need to research the brand or contact the seller for more details.