Geology Word of the Week: P is for Pleochroism

def. Pleochroism: 1. An optical property found in many minerals in which a crystal is able to absorb different wavelengths of transmitted light depending on the orientation of the crystal. 2. A useful characteristic for identifying minerals in thin section with an optical microscope. 3. A color-shifting mirage that adds extra pizazz and pop to certain gemstones. Pleochroic crystals are the chameleons of the mineral world. Pleochroic means “many-colored” in … Continue reading Geology Word of the Week: P is for Pleochroism