Definition: Apophyllite, also known as chalcedony, is a common crystal that forms when calcium oxide reacts with water. It is characterized by its yellow-green or blue hue due to the presence of iron and aluminum ions. Its chemical formula is CaO·Fe2O3•Al2O3. This compound was named after the ancient Greek philosopher and astronomer Porphyry (fl. 1080-1140 BCE), who recognized it as an unusual mineral in his collection.
closed bracket.
what should be said.