Moldavite is a tektite from a meteor crash that occurred 15 million years ago in the Bohemian Plateau of the Czech Republic. One of the four known tektites, first found in 1787 in the Moldau River , but the origin are the Nordlingen e Steinheim craters in Germany, few hundreds kilometres far.
Similar to obsidian or volcanic glass, in his structure we can see bubbles and curved swirls. The hardness is 6 to 6.5 and the silica content is very high: about 80%. Other minerals are: Iron,Magnesium,Calcium,Aluminum,Potassium and Sodium.
May be use in jewellery with care.