mineral

Zircon

Zircon (Zirconium Silicate - ZrSiO4)

Hardness: 7.5; Color: Red-brown to orangey-brown; Luster: Adamantine to vitreous; Crystal structure: Tetragonal; Cleavage: Poor; Specific Gravity: 4.6-4.7.

Hardness: 7
Color: Red-brown to orangey-brown
Luster: Adamantine to vitreous

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7.5; Color: Red-brown to orangey-brown; Luster: Adamantine to vitreous; Crystal structure: Tetragonal; Cleavage: Poor; Specific Gravity: 4.6-4.7.

Formation & geological history

Formed in igneous rocks (granites, pegmatites) and metamorphic rocks. As it is highly resistant to weathering, it is often found in sedimentary deposits like river sands. It is one of the oldest minerals on Earth.

Uses & applications

Used as a primary source of zirconium metal, in industrial abrasives and ceramics, and as a gemstone when clear. Essential in geochronology for dating rocks.

Geological facts

Zircon contains trace amounts of radioactive uranium and thorium, which makes it perfect for radiometric dating. The oldest known objects of terrestrial origin are zircons from Western Australia, dated to 4.4 billion years ago.

Field identification & locations

Identified by its high density (feels heavy for its size), intense luster, and sub-conchoidal fracture. Often found in heavy mineral sands or embedded in granitic rock. Tip for collectors: check for a slight double refraction when polished.