The gemstone-mines at the Steinkaulenberg Hill are the last visible evidence for the mining-activities of our ancestors in the region of Idar-Oberstein. Former there were several more gemstone-mines (Freisen, Weiselberg, Gruenbach, Mambaechel, Scheuern ... ) in the Saar-Nahe region. Unfortunately from time to time it was impossible - because of the political situation - for the gemstone cutters from Idar to reach the mines.
The target of mining was a yellow-red jaspagate, and in smaller quantities red carnelians and “Saint-Stephen-Gems” . Carnelians are coloured by diffusly spread ironoxides - in the Saint-Stephen-Gems these ironoxides were concentrated in little spots and dots. For a faithful catholic this appearance of the gem is helping him to remind the martyr pain by arrows of Saint Stephen. All the other types of agate from the mine are having a lot of cracks and other damages, so that the miners offered these stones only exceptional to the gemstone-cutters.
But todays collectors are not disturbed by those little impurities - they love the spherulithic formations, the finelined banding and the richness of colours of these rare items. Under the microscope these agates are showing pseudomorphical changement from chalcedony to calcite (white) and little inclusions of brow ironcarbonate-crystals.
The simularity to the agates from the Setz Quarry, which is lying in the same lava-flow, sometimes leads to confusion.
Uninteresting for our ancestors were the awesome geodes, that could be found at the Steinkaulenberg. In this geodes collectors are able to find very unusual quartz twin formations, which are described in the article linked here (only in german).
More informations about thegemstone-mines and the gemstone region of Idar-Oberstein you´ll find under www.edelsteinminen-idar-oberstein.de