Moldavite is the world's most famous tektite and the most important in gemology. It is also one of the gems that has caused most dispute in the world for its extra-terretrial origin. Although it was officially discovered in 1878, it is known that it was used long before that. There are traces of its use as far back as 29.000 years. As with all tektites, it is the result of the impact of a meteorite on Earth's surface, which in this case occurred 15 million years ago. It is found near the Moldau River, north of Prague. The fragments are always small-sized, typically bottle-green, and their surface unmistakably rugged. It is much appreciated by esoteric people.