General terminology Moldavite-a tektite which formed 14.8 million years ago and is named after the Moldau river (also called the Vltava river) in the Czech Republic. It is comprised of approximately 78-82% silica along with aluminium oxide, iron oxide, calcium oxide, magnesium oxide and calcite (calcium carbonate) Vltavín-the Czech name for Moldavite in the Czech … Continue reading Guide to the Terminology of Moldavite