Twinned staurolite crystals. Staurolite is a hydrated aluminium silicate mineral that contains iron,magnesium and zinc in variable ratios. The colour varies from red-brown to black,and it can also have white streaks in it. It occurs in metamorphic rocks. The crystal structure is monoclinic and it usually forms prism-shaped crystals,though here the crystals are twinned. Crystal twinning occurs when two crystals grow together,forming an interlocked twinned structure. These samples are examples of penetration twinning | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wiersma, Dirk |
Bildgröße: | 5014 px × 3543 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |