This vintage 2-strand necklace is made of Swarovski aurora borealis beads in graduated sizes.
The longer strand is 14 1/4" and the shorter is 12 1/4". Including the silver-tone strand connectors and the extender chain, the maximum length of that shorter strand is 17".
These faceted crystal oval beads are Swarovski's 5200 shape, they are alternated with crystal bicones for flexibility of the strands. The largest beads are 18mm. Condition overall is very fine with some light surface wear to the AB finish but no cracks or chips.