pumice

"The teacher was noticing students who were not paying attention in class. "

"The Ellesmere Island Volcanics are a Late Cretaceous volcanic group of volcanoes and lava flows in the Qikiqtaaluk Region of northern Ellesmere Island, Nunavut, Canada."

"After years of playing guitar, he developed calluses on his fingertips. "

"The geology class studied a sample of pyroclastic from Mount Vesuvius. "

"The box containing my old toys was stored in the attic. "

"He examined the crime scene for clues."

"He listened carefully to his mother's concerns, feeling sorrowful about her disappointment. "

"The geologist studied the rocks in the park. "

"The melted butter solidifies in the refrigerator. "

"The volcano's frequent eruptions sent plumes of ash high into the sky. "

"The stone had an igneous appearance."

"The demolition crew carefully handled the explosive before the building implosion. "