Natural jadeite jade graduated bead sterling silver necklace

This is an amazing natural / untreated jadeite jade graduated bead sterling silver necklace. The beads are 6.5 to 9.5 mm in diameter. They each have their unique color, pattern, and inclusions. One bead has a natural cavity on it (please see the last picture). The clasp is made of solid sterling silver and is stamped 925 on its side. The necklace measures 18.5 inches end to end. In excellent vintage condition.