22-05-2024, 20:12
http://lh3.googleusercontent.com/-vfZ1Xw...2520cm.jpg
Phlogopite in glimmerite-carbonatite. Carbonatite is igneous rock with highly unusual carbonate composition (white mineral is calcite). It is usually phlogopite when biotite group mica is associated with carbonate minerals in igneous or metamorphic rocks. Siilinjärvi, Finland. Width of sample 9 cm.