Simplify the following text for a Grade 8 native English-speaking person.
Original: The most common naturally occurring minerals are the very insoluble barium sulfate , BaSO4 ( barite ) , and barium carbonate , BaCO3 ( witherite ) .
Simplified: Barium is found as barium sulfate ( barite ) and barium carbonate ( witherite ) in the ground . Both of these minerals do not dissolve in water .