Berghotel Thundereggs

An extremely rare location in the city of Oberhof (one of several, it seems - see here for others). Like many here, it is described as only lasting/accessible for a short time. They have a rich brown matrix, sometimes showing very intricate texturing. In terms of the core, none of the specimens I have seen have classic agate, instead being filled with green silicified mud, various forms of quartz, etc. Close-up, they are exceptionally beautiful - see the detail shots for more.