mineral

Sulfur

Native Sulfur (S)

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

Hardness: 1
Color: Bright yellow to yellowish-brown
Luster: Resinous to greasy

Identified May 30, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed primarily as a sublimation product from volcanic gases around fumaroles, or as a byproduct of bacterial action on sulfate minerals like gypsum. It can also be found in salt domes and sedimentary deposits.

Uses & applications

Extensively used in the manufacture of sulfuric acid, fertilizers, gunpowder, matches, insecticides, and the vulcanization of rubber. Highly valued by mineral collectors for its vibrant color.

Geological facts

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

Field identification & locations

Identified in the field by its distinct bright yellow color, low hardness (can be scratched by a fingernail), and the faint odor of rotten eggs when rubbed or struck. Common locations include Sicily, Italy; Texas and Louisiana, USA; and volcanic regions like Indonesia.