Cobalt glass is precious, in fact I bought what I thought was a cobalt glass votive in Ocean Beach, and the color peeled off. Talk about shabby goods. Don't worry it's not this glass in this pendant,this is genuine cobalt BLUE seaglass . The Sea glass piece is bezel set in fine silver, which has been embellished with 1mm sterling ball chain and 18 gauge sterling wire. This eye catching pendant has been cleverly attached to a delicate sterling silver chain with a lobster clasp. Made On MArs has been stamped onto the backside, to remind the owner that each piece is a unique treasure.