The glass container manufacturing industry is rallying around “Close the Glass Loop,” an ambitious campaign to increase the quality and quantity of recycled glass collected across Europe.   Recycled glass, called “cullet,” is one of four ingredients – sand, limestone, soda ash, cullet–used in the glass-making process.    For example, glass containers made by O-I Glass have an average of 38% recycled glass; in Europe, that number is as high as 90%.   Glass packaging has numerous earth...