metamorphic

Tiger Iron / Banded Iron Formation

Banded Iron Formation (SiO2 with Fe2O3 and FeOOH)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs); Color: Golden-brown, metallic grey, and red bands; Luster: Silky to sub-metallic; Crystal Structure: Trigonal (as quartz/hematite microcrystals); Cleavage: None; Specific Gravity: 2.6 - 3.4

Hardness: 7 (Mohs)
Color: Golden-brown, metallic grey, and red bands
Luster: Silky to sub-metallic

Identified May 4, 2026More metamorphic →

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Physical properties

Formation & geological history

Formed approximately 1.8 to 2.5 billion years ago in Precambrian sedimentary basins. It is a metamorphosis of tiger's eye, red jasper, and hematite layers through tectonic pressure and heat.

Uses & applications

Primarily used for ornamental carvings, jewelry (cabochons), and as a high-quality decorative stone in interior design. Also historically a minor ore of iron.

Geological facts

This specimen is essentially a mixture of three distinct minerals: Golden Tiger's Eye, Red Jasper, and Hematite. It is mostly found in the Hamersley Ranges of Western Australia.

Field identification & locations

Identify by its distinct alternating layers of yellow/gold (chatoyant), deep red, and dark metallic grey. It is heavy for its size due to the iron content. Found primarily in Australia and South Africa.