What is 859 mark on jewelry?

The mark "859" on jewelry typically indicates the purity of the metal used in the piece. In this case, "859" likely refers to an alloy that is 85.9% pure, commonly used in silver jewelry. This level of purity is often denoted as 925 sterling silver, which means the metal is composed of 92.5% silver and 7.5% other metals for added strength and durability.