Identification guide · Sedimentary Rocks
How to Identify Laterite
Laterite is usually red, orange, and brown with a dull luster and is opaque. It has a Mohs hardness of 4. A steel knife blade (Mohs 5.5) scratches it; a copper coin does not. Its streak is red brown to yellow brown. It is most often confused with Ironstone, Bauxite, and Goethite; the tests below separate them.
Laterite identification checklist
| Color | Red, Orange, Brown, Yellow brown, Purple red | Look at a clean, dry surface in daylight. Color zoning, banding or spots are as diagnostic as the hue. |
|---|---|---|
| Luster | Dull | Compare a fresh surface with glass and metal; this luster is softer than either. |
| Transparency | Opaque | Hold a thin edge up to a bright light and note whether light passes through. |
| Mohs hardness | 4 | A steel knife blade (Mohs 5.5) scratches it; a copper coin does not. |
| Streak | Red brown to yellow brown | Drag a corner across unglazed porcelain (the back of a bathroom tile) and check the powder color. |
| Cleavage | Variable by mineral grains | |
| Fracture | Earthy to uneven | |
| Specific gravity | 2.7 | Ordinary rock-like heft (specific gravity about 2.7), similar to quartz. |
Laterite look-alikes and how to tell them apart
Both sit near Mohs 4, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Laterite vs Ironstone →
Laterite is harder (Mohs 4) than Bauxite (Mohs 1–3), so Laterite will scratch Bauxite and not the other way round. A fingernail (Mohs 2.5) scratches it easily. Laterite vs Bauxite →
Goethite is harder (Mohs 5–5.5) than Laterite (Mohs 4), so Goethite will scratch Laterite and not the other way round. A steel knife blade (Mohs 5.5) scratches it; a copper coin does not. Laterite vs Goethite →
Sandstone is harder (Mohs 6) than Laterite (Mohs 4), so Sandstone will scratch Laterite and not the other way round. A steel knife blade (Mohs 5.5) scratches it; a copper coin does not.
Field tips
- Look for earthy red, orange, brown, or yellow-brown colors.
- Laterite can be porous, nodular, or strongly weathered.
- It often occurs near surface weathering profiles rather than fresh bedrock interiors.
- Do not confuse laterite with ordinary red sandstone unless texture and context support it.
Laterite identification FAQ
How can you tell if a rock is Laterite?
Check the color (red, orange, brown, and yellow brown), the dull luster, a Mohs hardness of 4 and a red brown to yellow brown streak. Photographing it with the StoneSnap app gives a match in seconds.
What is the hardness of Laterite?
Laterite has a Mohs hardness of 4. A steel knife blade (Mohs 5.5) scratches it; a copper coin does not.
What is the difference between Laterite and Ironstone?
Laterite (Mohs 4, dull luster) and Ironstone (Mohs 4, dull luster) look alike, but hardness, streak and heft usually separate them. See the full Laterite vs Ironstone comparison for a side-by-side table.
Is Laterite worth anything?
Entry-level Laterite specimens sell for around $1, typical collector pieces about $10, and premium examples $75 or more depending on size, quality and locality.
What color is Laterite?
Laterite is most often red, orange, brown, and yellow brown. Color varies with impurities and locality, so confirm with hardness and luster rather than color alone.
