Stilbite with Heulandite

specimen number:
1052581

location:
St Andreasberg, Braunlage, Goslar, Lower Saxony, Germany

description:
Colorless crystals of stilbite measuring to 1.5 cm in size across the top of matrix with crystals of heulandite. In good condition. The specimen comes with an antique label, this noting that the piece was collected in 1893. This is shown at the end of the video.

he Saint Andreasberg mining district, situated within the Upper Harz mountains of Lower Saxony, Germany, is a world-famous historic mineral locality celebrated for producing spectacular silver ores and exceptional, highly diverse crystals of calcite, fluorite, and galena. Geologically, this historic deposit is unique within the Harz region due to its complex network of silver-rich hydrothermal veins that cut through a sequence of Devonian to Carboniferous-age sedimentary rocks, including shales, graywackes, and cherts. These veins were mineralized during late Paleozoic to Mesozoic rifting events when deep-seated, hot brine solutions circulated through the faults, depositing high-grade native silver, dyscrasite, and pyrargyrite alongside superb secondary minerals in large, open vugs. Historically, organized underground silver mining at Saint Andreasberg began in the late fifteenth century, around 1487, and reached its primary industrial peaks during the sixteenth and eighteenth centuries under Royal Hanoverian administration. Dozens of deep shaft operations, such as the famous Samson mine and the Saint Andreaskreuz mine, exploited these deep vein systems until declining ore grades and severe water-management issues made extraction unprofitable, leading to the systematic shutdown of all major silver mining operations by 1910.

J. Brunner was a notable German mineral dealer based in Magdeburg during the late 19th and early 20th centuries, a period when the city served as a significant hub for European trade and industry. His dealership was recognized for supplying high-quality mineralogical and geological specimens to both private collectors and academic institutions, often focusing on the diverse mineral wealth of the Harz Mountains and the Stassfurt salt deposits. Historically, Brunner played a role in the wider distribution of rare species and classic German locality pieces, with his name frequently appearing on historical specimen labels that are still preserved in museum archives.

Questions about this specimen?
Send an email or call us: 314-341-1811.