What does NB mean stamped on the inside of a ring?

The stamp "NB" on the inside of a ring typically stands for "Nordic Bronze," indicating that the ring is made from a specific type of alloy that includes copper and other metals, known for its durability and resistance to corrosion. It may also refer to the initials of a designer or manufacturer. If you're unsure of the specific meaning, it can be helpful to consult with a jeweler for clarification.