The so called “Nohfelder ryholitic range”, a petrografic formation of pale coloured, silica-rich vulcanic rocks, is allowing only a few possibilities for rock-hunting. One exception is the location “Teufelskanzel” (devils pulpet) at Leistberg Hill, one mile north of the village Oberthal. This location was known to our ancestors since centuries - but it became very popular to agate-hunters in the late 1970ies. After a short, but very excessive used time the “rush” was terminated by a acclamation of a “natural reserved location” at this place.
Today no collecting at all is allowed at this location.
The agates from the “Teufelskanzel” are Lithophysae (“Thundereggs”). Usually they are showing a brecciated formation of rhyolite and chalcedony in the center. Star-shaped or ring-shaped formations do only occur in the smaller specimen. The bigger ones (Lithophysae up to a size from 30 inches were found) do have very delicate patterns. The collectors like these patterns very much because by using associations they can explain their subjective idea of a specimen. Some agate-collectors are able to see everything from “wild boars” up to the “queen of the nigth” in their favourite specimen.
The colours of those lithophysae are usually dark - but some are showing brigth blue, yellowish, pink or red colours. A very unusual aspect of formation is giving these agates a special position worldwide. They are showing a very strong fluorescence under longwave- UV-light, caused by inclusions of uranium.
In may 2013 I published an article about this agate-finding location in the mineral-magazine “Lapis”. All pictures, that were made for this article, can be seen here.