Why is it called Mason jar?
The Mason jar is a molded glass jar used in home canning to preserve food. It was named after American tinsmith John Landis Mason, who patented it in 1858. The jar’s mouth has a screw thread on its outer perimeter to accept a metal ring or “band”.
Regarding this, Why are old mason jars blue? Feeling Blue
Those blue mason jars were mass produced until 1937 using sand from around Lake Michigan.