Extrémně tmavý, 104 g vážící vltavín z Chlumu nad Malší (jižní Čechy) ve sbírce Národního muzea v Praze
Extremely dark, 104 g heavy moldavite from Chlum nad Malší (southern Bohemia) in the collection of National Museum, Prague
Klíčová slova
Abstrakt
In the collection of the National Museum in Prague, there is one large moldavite from Chlum nad Malší sandpit in Southern Bohemia weighing 104.3 grams. Its size together with extremely dark colour raised suspicion that it is rather a tektite of an Australasian origin, perhaps indochinite. A tiny fragment was taken from the tektite to determine its chemical composition. Based on the content of K2O, Na2O, FeO and TiO2 it is concluded that this tektite belongs to moldavite group. Its unusually dark colour is due to the relatively higher content of FeO and TiO2 and relatively low content of CaO and MgO.
Soubory
Reference
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