Sterling silver chain with dyed blue corundum beads. The bead size will be approximately 1.5x3mm. This necklace has a spring ring clasp and is 16 inches with a 1.5-inch extension to adjust the length. .925 sterling silver. ABOUT CORUNDUM STONES: Corundum is the exact same mineral, but lower-quality equivalent, to ruby and sapphire. These stones go through a chemical process to even and enhance their color and develop their natural characteristics, which can include heating and dye. This results in a mineral equivalent that is a beautiful and affordable option for wearing large carat weight stones in the corundum families of rubies and sapphires