mineral
Fulgurite
Fulgurite (Lechatelierite / Vitreous Silica)
Hardness of 5.5 to 6.5 on the Mohs scale, typically brown, tan, or gray, with a glassy to vitreous luster. Forms as hollow, branching tubes of melted quartz sand or soil.
Identified More mineral →
Explore Fulgurite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 5.5 to 6.5 on the Mohs scale, typically brown, tan, or gray, with a glassy to vitreous luster. Forms as hollow, branching tubes of melted quartz sand or soil.
Formation & geological history
Formed instantly when a high-voltage lightning strike (often exceeding 30,000 amperes) hits quartz sand or soil, melting the material at temperatures above 1,800 degrees Celsius.
Uses & applications
Collected by enthusiasts, used in scientific research regarding ancient lightning strikes and paleoclimatology, and occasionally crafted into unique jewelry.
Geological facts
Often referred to as 'fossilized lightning', fulgurites preserve the path of the electrical discharge and can sometimes contain tiny trapped gas bubbles or even microscopic bits of meteoritic material.
Field identification & locations
Found in sandy deserts, beaches, or high-altitude mountain peaks where lightning strikes are frequent. Identified by its tubular, glassy, or fused sandy exterior.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Soil with Mineral Detritus and Quartz Fragments
Regolith / Silicate Mineral Aggregate
sedimentary
Limonite / Goethite (Iron Ore Mineral nodule)
FeO(OH)·nH2O / FeO(OH)
mineral
Schist
Schist
Metamorphic
Septarian Pebble
Septarian nodule / Concretion
sedimentary
Potassium Feldspar (Orthoclase)
Orthoclase (KAlSi3O8)
mineral