from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A slender, usually tubular body of glassy rock produced by lightning striking and then fusing dry sandy soil.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. glass formed by a lightning strike melting sand or other material

from the GNU version of the Collaborative International Dictionary of English

  • n. A vitrified sand tube produced by the striking of lightning on sand; a lightning tube; also, the portion of rock surface fused by a lightning discharge.

from The Century Dictionary and Cyclopedia

  • n. A tube formed, usually in loose sand, but sometimes in the solid rock, by lightning; a lightning-tube.
  • n. An explosive of the nitroglycerin class, used for blasting: similar to dynamite, but the nature of the dope has not been disclosed by the inventor.


from The American Heritage® Dictionary of the English Language, 4th Edition

Latin fulgur, lightning; see fulgurate + -ite1.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin fulgur.


  • The unheated soil associated with the fulgurite is a tan, sandy silt.

    Fulgurite - The Panda's Thumb

  • I found a fulgurite, once It was broken off near where the boiled sand first fused to glass and ended about six inches down the stem.

    Making Light: Pretty rocks

  • Is the light grey stone on the right part of the matrix surrounding the fulgurite?

    Fulgurite - The Panda's Thumb

  • The photographer says that the entire fulgurite is about 10 cm in diameter, but this photograph is only a detail.

    Fulgurite - The Panda's Thumb

  • During the lightning strike, the soil heated up to the gray color shown in this photo, forming the exterior of the fulgurite, and individual grains are cemented together with a small amount of glass.

    Fulgurite - The Panda's Thumb

  • It was a fulgurite, Laura told him, sand fused the moment it was struck by lightning.

    The Tenth Circle

  • "The lab reported the explosive had been chemical - fulgurite-B, the name is."

    Time Patrolman

  • Also found in the altar trench was a sample of fulgurite or petrified lightning.

    EurekAlert! - Breaking News

  • It is not clear if the fulgurite was formed on the mountain-top or if it was brought to the site as a dedication to Zeus.

    EurekAlert! - Breaking News

  • The fulgurite was interesting–I’ve never found one although I have seen the shatter cones in the rock around Sudbury from the meteorite that planted the nickel mines 1.8 billion years ago.

    Photo Contest Vote: Minerals - The Panda's Thumb


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  • A naturally forming hollow glass tube; created when certain types of sand are struck by lightning.

    September 17, 2008