Tektite

14.5 g.
Argentina
"Tektites (from Greek τηκτός "tēktos", molten) are gravel-size bodies that are composed of black, green, brown or gray, natural glass that are formed from terrestrial debris ejected during extraterrestrial impacts.

The overwhelming consensus of Earth and planetary scientists is that tektites consist of terrestrial debris that was ejected during the formation of an impact crater. During the extreme conditions created by an extraterrestrial, hypervelocity impact, near-surface terrestrial sediments and rocks were either melted, vaporized, or some combination of these and ejected from an impact crater. After ejection from the impact crater, the material formed millimeter- to centimeter-sized bodies of molten material, which as they re-entered the atmosphere, rapidly cooled to form tektites that fell to Earth to create a layer of distal ejecta hundreds or thousands of kilometers away from the impact site"