Tektite

Tektites are small lumps of natural glass, from a few millimetres to a few centimetres across, coloured black, green, brown or grey. The name comes from a Greek word meaning molten, and the geologist Franz Eduard Suess coined it. Earth and planetary scientists now overwhelmingly agree that they began as rock and sediment of the Earth's own crust, melted by a meteorite strike, flung far from the crater and cooled as they fell back through the air; an older idea that they came from volcanoes on the Moon has lost its support. They look like obsidian but differ from it: they are glass all through, with no tiny crystals, hold almost no water, and although rich in silica they are chemically closer to shales than to volcanic rock. Splash-form tektites set as spheres, teardrops and dumbbells, while the layered Muong Nong kind can be more than 10 centimetres across. Most are found in four wide strewn fields, in Australasia, central Europe, the Ivory Coast and North America, and the green moldavites of the Czech Republic are one regional type. Hall treats the tektite as a stone from outer space, ties it to communication with other worlds, higher knowledge, letting go of bad experiences, telepathy and balancing the chakras, and says it was traditionally worn as a talisman for fertility.