calcite

"While walking to school, Sarah found a lost wallet on the ground. "

"My doctor recommended I take a calcium supplement to strengthen my bones. "

"He distributed the bread amongst his followers."

"The ancient Roman ruins were made of strong marble. "

"The teacher wrote on the blackboard with a piece of chalk. "

"The antacid tablet contained a carbonate to neutralize stomach acid. "

"The new school policy was widely discussed by parents. "

"The geologist found a beautiful mineral specimen in the rock collection. "

"The jeweler carefully inspected each crystalline before setting it in the ring. "

"The white cliffs were made of limestone, a rock formed from ancient seashells. "

"The children formed a circle to play duck, duck, goose. "

"The students were mostly quiet during the presentation. "