Q. What made the old Ball jars blue?
A. I've had several people ask this question and didn't really know myself so did some digging and research and found this great site that explained it nicely... and quite interestingly... We've all learned something...
"It’s all in the sand.
Most of us know glass is made from sand. You might not have known that glass color comes from the mineral content in the sand that’s used to make the glass. We wondered what was different about the sand that Ball used. How come no other company had sand that made their jars that particular shade? And why did Ball stop making jars in the signature color?
Turns out, the sand comes from an onetime Indiana landmark. According to the public library in Michigan City, Indiana:
“Once Indiana’s most famous landmark, Hoosier Slide was a huge sand dune bordering the west side of Trail Creek where it entered Lake Michigan. At one time it was nearly 200 feet tall, mantled with trees. Cow paths marked its slopes and people picnicked upon its crest. Climbing Hoosier Slide was very popular in the late 1800s with the excursionist crowds who arrived in town by boat and train from Chicago and other cities. The summit, where weddings were sometimes held, afforded an excellent view of the vast lumberyards which then covered the Washington Park area.
“With the development of Michigan City, the timber was cut for building construction and the sand began to blow, sometimes blanketing the main business district of the town on Front St., which nestled near its base.
“When it was discovered that the clean sands of Hoosier Slide were useful for glassmaking, the huge dune began to be mined away. Dock workers loaded the sand into railroad cars with shovel and wheelbarrow to be shipped to glassmakers [and other places].
“Over a period of 30 years, from about 1890 to 1920, 13 1/2 million tons of sand were shipped from Hoosier Slide until the great dune was leveled. By the 1920s, nothing remained of the giant dune.”
Here’s a telling excerpt from a memoir on emichigancity.com (the man is writing about his father):
“For twenty-five years, six days a week, he pushed an iron-wheeled wheelbarrow, moving sand from Hoosier Slide onto gondola carts headed for the manufacturing of canning jars.”
I don’t know exactly what geologic event caused the Hoosier Slide’s sand to have just the right mineral mix to create the famous Ball Blue glass color, but it was apparently something special that didn’t turn up in any other fruit jar maker’s glass.
Once the Hoosier Slide sand was all used up, Ball had to get another source, and the glass formula was forever changed. No more pretty Ball Blue. There are many shades of aqua and blue in the fruit jar world, but only the one Ball Blue."