Pewter is a composition metal made up of mostly tin (usually 91%), antimony and copper. The latter two materials are added to provide strength and durability to the metal. The higher the tin content, the greater the silver appearance. When tin is mined, there are trace amounts of lead in the metal. The FDA has strict guidelines for lead content in metal. Pewter undergoes a lead removal process when it is being used for jewelry/bead/finding components. When you see a label that says “lead-free pewter”, it is referring to this process.