Navajo Pearls handcrafted by renown Navajo artist Rose Martin, these beads are stunning. Set in solid sterling silver. The necklace measures 26" in length with a 2" extender. The largest bead measures 25 mm and tapers down to 12 mm. Her combination of round, saucer and cylinder styled shapes is very unusual. They have anice weight to them that make them feel substantial but comfortable. Truly a one of a kind necklace. MEDIUM LARGE ROSE MARTIN BEADS Navajo Pearls are traditionally made sterling silver beads. Silver beads are a traditional art form for Diné silversmiths, and the beads have as many expressions as there are artisans.... Making the beads is a time-consuming process. Each bead begins with silver that has to be melted, rolled and cut. Sterling silver Is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually copper. The sterling silver standard has a minimum of 925 purity. SILVER, for example 99.9% pure silver, is relatively soft, so silver is usually alloyed with copper to increase its hardness and strength. Sterling silver is prone to tarnishing, and elements other than copper can be used in alloys to reduce tarnishing, as well as casting and fire scale Oxidized silver (black coloring in the silver) is a process that many jewelers use to give sterling silver a black patina. It gives the jewelry an antique or tarnished look. The process consists of taking clean sterling silver and using a chemical (liver of sulphur) to treat it to speed up the tarnishing effect.