Moldavite is an amorphous tektite consisting of green glassy natural material. The hardness according to the Mohs hardness scale (1 to 10 where diamond has a value of 10) is 6.5 to 6.9. The Moldavite was created about 15 million years ago by the impact of two meteorites of 1.5 km and 150 meters in diameter respectively, which simultaneously impacted at an angle of 30-50 degrees to the Earth's surface at a speed of about 20 km /second. Almost certainly the Nördlinger Ries and the Steinheim crater in southern Germany respectively are the impact craters of this. These impacts released an enormous amount of energy, 1.8 million times that of the atomic bomb dropped on Hiroshima. Enormous pressures were achieved at a temperature of more than 30,000 degrees Celsius. As a result, large amounts (in total about 150 km³) of sand and earth were melted and flung into space. After reentering the atmosphere, these fragments of terrestrial matter, mixed with the extraterrestrial matter, solidified and fell back to the ground in a so-called 'stretching area' that roughly covers the area of the Czech Republic. A very small part of it solidified into Moldavite. Contrary to what most claim, the Moldavite is found in several places in the Czech Republic. Smaller scattering areas, independent of that in the Czech Republic, are in northern Austria and parts of Germany bordering the Czech Republic. The most precious Moldavite is found at the upper reaches of the Vltava, in the south of the Czech Republic. This one has a green color with small inclusions. This stone is also called the Czech Emerald and is incorporated in the crown jewels of the Czech Republic. The stones found in Moravia are brown in color and less expensive. Because the sites of Moldavite are quickly exhausted, this stone is becoming increasingly valuable.