Tektites are irregularly and sometimes, intricately shaped nodules and blobs of a glassy substance that are thought to be the products of melted terrestial rocks (possibly formed by the impact of large meteorites on the Earth’s surface). They are the driest known minerals with a low water content of 0.005% and their name comes from the Greek word ‘tektos’, meaning ‘molten’.

They also often contain coesite (a highly dense silica polymorph), nickel-iron spherules, and baddeleyite (a zircon oxide mineral produced at very high temperatures during shock metamorphism), which lend evidence to a meteorite impact origin.

Tektites have been found only in certain parts of the world, spread over large areas called strewn fields, mainly in low latitudes. The three major areas are south-east Asia (especially Thailand and the Philippines), Australasia; Caribbean-North America; and Ivory Coast, West Africa. About 100,000 tektites have been found in Australasia, the heaviest being 400 grams.

Some tektites, called Moldavites, are especially prized for their clarity and unique green color. Moldavites are found in a “splash field” centered around Moldavia in former Czechoslovakia and are believed to have come from a meteorite crater in Germany. Moldavites are sometimes cut as gemstones or put into jewelry as natural uncut pieces to show off their often eerie and beautifully intricate shapes.

Prehistoric men used tektites as implements and ornaments. There are tools made of tektites that date back to 4,000-6,000 B.C. and after the iron age (500 B.C.) tektites were worn as good luck charms.