What does 835 stamped on a neckless mean?

The "835" stamp on a necklace indicates that the piece is made of silver that is 83.5% pure, which is a higher silver content than the more common sterling silver standard of 92.5% purity. This mark is often found on jewelry from countries that follow the European standard for silver, such as the Netherlands and Germany. It signifies quality and can affect the value of the piece based on its silver content.