Looking for help finding information on Milk Jug

This piece was passed down from my grandmother who passed away at 96 years old in 2016. She has told be my whole life that this "Milk Jug" belonged to her mother who had used it as a milk jug since she was first married in the early 1900's. I have found writings from my oldest great aunt ( 15 years older than Grandma Chris) where she talks about being sent out with "The Blue Jug" to get milk. Grandma told me that her mom brought the jug everywhere she went in a wagon from Arizona to California. the jug has no markings I can find, but does not appear to be "hand Made", more like a production type pottery, though I am no expert. Looking for any help or guidance available from folks here on this forum.