| colours of bornite (brown), chalcocite (blue), and pyrite (creme). 2 Reflectance Reflectance relates to...internal reflections. Isotropic minerals, such as pyrite or galena, do not show bireflectance. Left: Radial...anisotropy. In rare cases, isotropic minerals, such as pyrite or galena, may show an anomalous anisotropy due...transmitted light). Left: The polishing hardness of pyrite (creme) is much higher than that of graphite (brownish...grey), which shows grooves at the contact with pyrite, leading to a strong relief. 4 Cleavage Cleavage |
