Amethyst druse

Even in antiquity, the violet-coloured variety of quartz amethyst was one of the most sought-after gemstones. During the Middle Ages it was still administered as a remedy for drunkenness and then deployed in the modern era as a polished stone in holy artefacts, such as goblets, crosses and rings. By no later than the 16th century, Freiburg lapidaries also polished rare amethyst finds from regional deposits, before the arrival of hardstone from the Saar-Nahe area. At the beginning of the 1950s, a student (Klaus Burgath) discovered numerous material remnants of a medieval grinding mill on the Kartäuserstraße in Freiburg. In addition to Bohemian garnet, they had also milled various types of chalcedony, rock crystal and amethyst. However, the highest quality of hardstone was discovered as late as the late-19th century in Uruguay by European migrants. Since then, amethyst has been widely used in modern jewellery and engravings of all kinds. The giant druse amethyst geode pictured was found in the flood basalts of the Rio Grande do Sul basalt group in southern Brazil measuring up to 1,800 m. These volcanic rocks over 100 million years old contain numerous mineralised gas bubbles and are mined to this day for amethyst and agate.