This is an incredibly pretty vintage Enamel Guilloche necklace.   It features a ring of 6 yellow stars on a baby blue guilloche enamel background, with another yellow star at its centre.   

The reverse is plain silver and it opens up into a good sized round locket, which is  empty and ready to hold a keepsake or photo of your own.  The bale is marked for Sterling Silver. It will need frames and covers. 

The locket measures 2.3cm in diameter, the chain length 16 inches, and weight is a healthy 6.41g.

Please have a look at the pictures and video, and dont hesitate to get in touch if you need any further information.