What does B2 mean stamped in a ring?

B2 stamped inside a ring typically indicates the ring's material or metal content, such as 925 sterling silver, which consists of 92.5% silver and 7.5% other metals. The "B" in B2 is likely an abbreviation for "Britannia," a quality mark commonly used in the UK to denote the standard of silver purity.

Therefore, B2 in a ring indicates that the ring is made of 925 sterling silver, meeting the specific standards set by the British hallmarking system for silver quality and purity.