| 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) |
| 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. |
| Die speziell auf die Bedürfnisse für Mineraliensammler abgestimmte Scurion 1500 mit UV Option wird primär in 2 Teilen und Zubehör geliefert. Auf der einen Seite der Lampenkopf mit Verbindungskabel und Durchführung für den Batteriekasten. Und dann der Batteriekasten, der in seiner geschwungen Form an ... moreDie speziell auf die Bedürfnisse für Mineraliensammler abgestimmte Scurion 1500 mit UV Option wird primär in 2 Teilen und Zubehör geliefert. Auf der einen Seite der Lampenkopf mit Verbindungskabel und Durchführung für den Batteriekasten. Und dann der Batteriekasten, der in seiner geschwungen Form an einen Flachmann erinnert. Zum Testen lag uns eine Version mit kurzem Kabel zur Befestigung von Lampenkopf und Batteriekasten am Helm vor. |