These are old Mexican earrings with a cobalt blue colored stone. Looks like there may be foil backing. Nice filigree work around the stone. Back of dangle portion marked Sterling & Mexico. The screw back is marked Alpaca. There is a makers flaw on one of the earring screw balls, it is not fully filled out. ( see photo). Never noticed it and I've had them for 30 plus years. I bought these in Oaxaca over 30 years ago. Size: 1 1/4" long x 1/2" wide. Please enlarge photo's as they are part of the description. Any questions ? just email and I will respond same day. You may combine items for shipping. I mail the same day as payment received,before 3:00 p.m. Pacific time.