Sea glass is any broken piece of glass from a bottle of beer, to vintage headlights, to handmade pottery and beyond. All sea glass is at least 5 to 50 years old and sometimes up to 100 years old or more! This process is called ocean tumbled and it makes the gems completely smooth with no rough edges, this also means we NEVER use a machine to tumble! The wire used is either sterling silver, gold filled, or copper. All glass is sold by rarity and depending on where the stone was found. Thank you and Enjoy!