ktites

Ktites, also known as tektites, are natural glassy objects formed when terrestrial rocks are melted and ejected during large meteorite impacts. As the molten droplets travel through the atmosphere, they cool rapidly and land as glassy debris spread over broad strewn fields on Earth. Most ktites are silica-rich glasses whose compositions reflect the crustal rocks melted by the impact.

Ktites vary in size from millimeters to several centimeters and come in colors ranging from green to brown or black. A distinctive feature is their aerodynamic shapes: many exhibit teardrop or bottle-like forms produced by flight through the air, while others show conchoidal fractures or surface sculpting from rapid cooling and bombardment with atmospheric particles. In addition to individual specimens, tiny glass spheres known as microtektites are found in ocean sediments and continental deposits, recording widespread ejecta events.

Geographically, ktites occur in several recognized fields. The largest is the Australasian tektite field, followed by Central European tektites, which include the well-known moldavite. North American tektites form another important field. Moldavite, a green tektite from Central Europe, is widely studied and sometimes used as a gemstone. The study of ktites also includes microtektites, which provide evidence of impact processes at much larger scales and across different environments.

Ktites are scientifically significant because they preserve information about impact melt production, ejection dynamics, and atmospheric passage. Their distribution and composition help constrain the timing and scale of past impact events, making them valuable in planetary geology and paleoclimate research.