"On the skin, similar deposits can happen, which can clog pores and lead to acne breakouts," Hart says. That's not to mention that soap bonds with calcium ions, making it harder to rinse off the skin.

Your standard blackboard chalk is calcium carbonate, and sidewalk chalk is usually calcium sulfate. If you want to buy chalk for your home gym or to carry in your gym bag, make sure you’re ...

Hard water is water that contains high levels of minerals – particularly calcium and magnesium – which are picked up as it flows through porous rocks such as limestone or chalk.

Calcinosis cutis is when calcium collects in your skin, muscles, tendons, and connective tissue. Learn about the causes, symptoms, and treatment options for this condition today.

And you may hear it called calcium bentonite clay. People have eaten bentonite clay or put it on their skin for thousands of years. It’s been used to: Clean or protect skin; Heal skin infections ...