sedimentary

Lightning Stone / Fulgurite-impregnated or Septarian-like Agate

Silicon dioxide (Quartz/Chalcedony) with host rock matrix

Hardness: 7 on Mohs scale; Color: Gray, white, and translucent; Luster: Vitreous to waxy; Crystal structure: Microcrystalline (Cryptocrystalline quartz); Cleavage: None (conchoidal fracture); Specific gravity: 2.60 - 2.65

Hardness: 7 on Mohs scale
Color: Gray, white, and translucent
Luster: Vitreous to waxy

Identified August 6, 2026More sedimentary →

Explore Lightning Stone / Fulgurite-impregnated or Septarian-like Agate in the encyclopedia →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich groundwater solutions in cavities or fractures of a host rock over millions of years, often in volcanic or sedimentary environments.

Uses & applications

Collected as a unique geological specimen, lapidary art, and metaphysical purposes.

Geological facts

This specimen displays a striking natural pattern resembling a lightning bolt or rune enclosed within a chalcedony/agate matrix, making it a highly unusual and visually captivating natural formation.

Field identification & locations

Can be identified by contrasting matrix colors and distinct inclusion shapes within a translucent chalcedony body. Often found by rockhounds in gravel beds, creek beds, and areas with historical volcanic or hydrothermal activity.

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