mineral

Sulfur

Native Sulfur (S)

Hardness: 1.5-2.5 on Mohs scale; Color: Bright yellow to pale yellow; Luster: Resinous to greasy; Crystal Structure: Orthorhombic; Cleavage: Poor; Specific Gravity: 2.0-2.1

Hardness: 1
Color: Bright yellow to pale yellow
Luster: Resinous to greasy

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 1.5-2.5 on Mohs scale; Color: Bright yellow to pale yellow; Luster: Resinous to greasy; Crystal Structure: Orthorhombic; Cleavage: Poor; Specific Gravity: 2.0-2.1

Formation & geological history

Formed primarily as a sublimate from volcanic gasses near fumaroles, or as a byproduct of bacterial action on sulfate minerals like gypsum in sedimentary environments. Common in evaporite deposits.

Uses & applications

Major source of sulfuric acid, used in the manufacture of fertilizers, matches, gunpowder, insecticides, and in the vulcanization of rubber. Collected by mineral enthusiasts for its vivid color.

Geological facts

Sulfur has been known since ancient times and is referred to as 'brimstone' in the Bible. It burns with a distinctive blue flame and emits a suffocating odor of sulfur dioxide gas.

Field identification & locations

Identified in the field by its distinct bright yellow color and the faint smell of rotten eggs when rubbed or struck. Common in volcanic regions like Sicily, Iceland, or Yellowstone. Handle with care as it is brittle and heat-sensitive.