I agree they look like a more modern strand of Majorica or Mallorca imitation pearls. (Those are brand names but similar, and are made in Spain.) The clasp should say 925, typically the clasps are either silver or vermeil (gold plate over silver.)
I have various strands myself and know they are very well made, durable and attractive. As stated above, they are rather expensive if bought at retail, but there is a good resale market for them on eBay if you find they don't suit you.