Laterite
“Tropical soil turned to brick”
Laterite is an iron- and aluminum-rich residual deposit that forms through intense chemical weathering in tropical and subtropical climates. When exposed to air, it hardens irreversibly into a rock-like material, making it a natural building stone used across South and Southeast Asia for centuries.
goethite, hematite, gibbsite (aluminum hydroxide), kaolinite, quartz
Western Ghats (India), Southeast Asia, West Africa, northern Australia, Amazon Basin (Brazil)
2-4 (hardens over time)
The temples of Angkor Wat in Cambodia are built from laterite blocks — the soft material was easy to quarry when wet, then hardened like brick once exposed to sun and air.
Test Your Knowledge
Why is laterite found exclusively in tropical and subtropical regions?
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