| Iin 1546 Georgius Agricola reported about a white metal which is fused to the Rammelsberg lead and silver melter and that you could scrape off. He called this metal "contrefey", because it could imitate gold. Agricola did not recognize that this metal was zinc. He further observed that a similar met ... moreIin 1546 Georgius Agricola reported about a white metal which is fused to the Rammelsberg lead and silver melter and that you could scrape off. He called this metal "contrefey", because it could imitate gold. Agricola did not recognize that this metal was zinc. He further observed that a similar metal, which he named from some unknown reasons "ZINCUM" arose under similar circumstances in Silesia during smelting. |
| Im Saarland ist der in Oberer, Mittlerer und Unterer Teil geteilte Buntsandstein, der frühesten Abteilung der Trias, nur mit den beiden jüngeren Stufen vertreten. Der Untere Buntsandstein ist nicht zu finden. In St. Arnual, am Ostabhang des Sonnenberges bei Saarbrücken, sind diese beiden Altersstufe ... moreIm Saarland ist der in Oberer, Mittlerer und Unterer Teil geteilte Buntsandstein, der frühesten Abteilung der Trias, nur mit den beiden jüngeren Stufen vertreten. Der Untere Buntsandstein ist nicht zu finden. In St. Arnual, am Ostabhang des Sonnenberges bei Saarbrücken, sind diese beiden Altersstufen eindrucksvoll aufgeschlossen. Folgt man den sogenannten Felsenwegen entlang der Saar, so erkennt man das Profil, einschließlich der Violetten Grenzzone, die die Trennung vom Mittleren zum Oberen Buntsandstein darstellt. |
| Aragonite is a calcium carbonate, chemically identical with calcite. The mineral calcite, however, differs from Aragonite due to its internal crystal structure. While the crystal system of calcite is trigonal, the system of aragonite is rhombic. Dense masses of small aragonite crystals are difficul ... moreAragonite is a calcium carbonate, chemically identical with calcite. The mineral calcite, however, differs from Aragonite due to its internal crystal structure. While the crystal system of calcite is trigonal, the system of aragonite is rhombic. Dense masses of small aragonite crystals are difficult to distinguish from calcite, but they are larger, they show a distinct habit. A lot of chapters in this portrait will give you much more details about this interesting mineral. Written and investigated by Peter Seroka. (Article in german) |
| The metal extraction by ore leaching (mostly copper) was about 1,000 years BC. known in the Mediterranean, but there are also barely no written records. The in the Middle Ages and in the following Renaissance well-known different procedures were first described in detail by Georg Agricola 1556 in hi ... moreThe metal extraction by ore leaching (mostly copper) was about 1,000 years BC. known in the Mediterranean, but there are also barely no written records. The in the Middle Ages and in the following Renaissance well-known different procedures were first described in detail by Georg Agricola 1556 in his book "De Re Metallica Libri XII". A contribution by Peter Seroka |