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Illinois now has an official State Rock.  Here’s What It Is – NBC Chicago

For decades, Illinois had a state bird and even a state tree, but a state rock had never been designated, although over 30 other states had an official rock or stone.

However, that changed on Monday.

At Lisle’s Morton Arboretum, surrounded by a group of middle school students who played a pivotal role in the selection process as well as state lawmakers, Illinois Governor JB Pritzker announced the official rock of the state – dolomite.

So what exactly is dolomite?

Dolomite is a sedimentary rock composed of dolomite, which is made of calcium and magnesium carbonate, and is similar to limestone.

Dolomite underlies nearly all of Illinois except for some northern counties and helps enrich the soil by providing valuable nutrients, according to a previous press release from Illinois Senate Democrats.

He was also responsible for the mineral rush at Galena in the early 1800s. To this day, you can visit Illinois’ dolomitic grasslands, including two in Cook County.

Grasslands both exist at the Sagawau Environmental Learning Center in Lemont and Theodore Stone Forest in Hodgkins, where the plants are “extremely hardy” and the ground is only a few inches deep, with dolomite underneath, according to Cook County Forest Reserves.

So how was the dolomite chosen?

Upon learning that Illinois did not have a state rock, students at Pleasantdale School in Burr Ridge and Maplebrook Elementary School in Naperville made the decision on them and decided that had to change.

So they interviewed regional geologists, visited museums, conducted research, and then engaged schools across Illinois.

The students created a ballot with three choices, and dolostone was the winner.

“With hundreds of schools participating and thousands of votes from Carbondale to Rockford to Chicago, the choice was clear – dolomite emerged victorious,” Pritzker said. “And it’s no surprise that dolomite, a specific form of limestone, formed most of our state’s bedrock in the early 1800s.”

Student involvement didn’t stop with the voting process, as they then worked with lawmakers to craft the legislation.

House Bill 4261, which sought to designate dolomite as the official state rock of Illinois, was first introduced in January and became a reality on Monday when Pritzker signed it into law.

Jennifer Lauermann, a Pleasantdale teacher whose students orchestrated the effort, said she was so proud of their effort and determination.

“Students, we started this project during a very crazy time, almost two years ago,” she said Monday. “And I was teaching in a cafeteria and… there was a learning moment that exploded. Two kids started talking about rocks and pretty much, we really focused a lot of the year about geology. I’ll never forget that.”

NBC Chicago

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