A globally exceptional find and a local specialty in the area of Sundwig in Sauerland, Germany: shiny, sparkling and water-clear quartz crystals with spectacular inclusions of fossil fungal mycelium and bacterial strands covered by yellow-brown iron oxides in iron stromatolites. The mineralization took place in karst caves in Devonian mass limestone (formations with large limestone masses, mostly reef limestone). See: Erdmannsdörfer, O.H. (1908) Journal of the German Geological Society Volume 60, 32-35
This is an oversized example of it, at least 6-10 times larger than anything else I have seen, because they are usually only a few millimeters in size and stick together in clusters.
