Moldavite
Moldavite is a rare type of meteoric/tectonic glass. Being natural glass (SiO2) it is amorphic rather than crystalline and has a hardness of 5 on the Mohs Scale. Forming due to the impact of meteors, tektites are given different names depending on where they fall to earth. The term Tektite usually refers to specimens from the Philippines, and they are usually black in colour. Moldavite only comes from the one meteor impact and is only found in Molvania, Czechoslovakia. It is one of the most highly valued tektites and is highly prized for it beautiful bottle green colour.