Big, thick, clear hand bicon faceted crystals with smaller faceted amethysts crystals in-between, this early Deco necklace. It is in excellent vintage condition without any chipped or cracked crystals, measuring about 18 1/2" to 19" in length. The stones are still on their original string, which was doubled so it's still pretty sturdy.
The stones have not been tested, but it is possible they are quartz. It is obvious under a loop that the smaller stones are amethysts due to the inclusions in the small stones. I cannot see any inclusions in the crystals but many times quartz was used in the earlier jewelry of this period. They may be man made or natural, I cannot say.
Regardless, the necklace is in excellent condition with just the locking c-clasp, and an extender chain added so it can be worn at a longer length. Origin unknown, circa 1930s.