Trivia: Blackboard Chalk Isn't Made of Chalk

Blackboard chalk is made of gypsum, not chalk.

Chalk is a type of limestone composed of the mineral calcite. Blackboard chalk used to be made from natural chalk, but it has since been replaced by compressed gypsum (calcium sulfate).

Newest 4
Newest 4 Comments

Login to comment.

Email This Post to a Friend
"Trivia: Blackboard Chalk Isn't Made of Chalk"

Separate multiple emails with a comma. Limit 5.


Success! Your email has been sent!

close window

This website uses cookies.

This website uses cookies to improve user experience. By using this website you consent to all cookies in accordance with our Privacy Policy.

I agree
Learn More