Gorgeous silver blue stone earrings & necklace set

Necklace has a silver chain, with a blue semi precious accent stone set in silver as a pendant. Earrings are a match to the pendant. This is a very classy, Jackie O style set that dresses up whatever you wear it with. Necklace hits just below the collarbone. I was asked if this is sterling silver. I can't find a stamp on the clasp or pendant that would evidence it's sterling, but it cleaned up absolutely beautifully in silver jewelry cleaner!