Identification guide · Sedimentary Rocks
How to Identify Evaporite
Evaporite is usually white, clear, and pink with a dull luster and is opaque. It has a Mohs hardness of 2.5. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Its streak is white. It is most often confused with Anhydrite, Gypsum, and Halite; the tests below separate them.
Evaporite identification checklist
| Color | White, Clear, Pink, Gray, Tan | 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 | 2.5 | A copper coin (Mohs 3.5) scratches it, but a fingernail does not. |
| Streak | White | Drag a corner across unglazed porcelain (the back of a bathroom tile) and check the powder color. |
| Cleavage | Variable by mineral grains | |
| Fracture | Uneven to crystalline | |
| Specific gravity | 2.2 | Noticeably light in the hand for its size (specific gravity about 2.2). |
Evaporite look-alikes and how to tell them apart
Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Evaporite vs Anhydrite →
Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Evaporite vs Gypsum →
Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Evaporite vs Halite →
Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
Field tips
- Look for pale, crystalline, sugary, or layered material associated with salt or gypsum minerals.
- Rock salt may be translucent and can dissolve readily in water.
- Gypsum-rich evaporites are softer and may show satin or crystalline surfaces.
- Do not taste unknown specimens; use safer tests and provenance instead.
Evaporite identification FAQ
How can you tell if a rock is Evaporite?
Check the color (white, clear, pink, and gray), the dull luster, a Mohs hardness of 2.5 and a white streak. Photographing it with the StoneSnap app gives a match in seconds.
What is the hardness of Evaporite?
Evaporite has a Mohs hardness of 2.5. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
What is the difference between Evaporite and Anhydrite?
Evaporite (Mohs 2.5, dull luster) and Anhydrite (Mohs 3–3.5, vitreous, pearly on cleavage surfaces luster) look alike, but hardness, streak and heft usually separate them. See the full Evaporite vs Anhydrite comparison for a side-by-side table.
Is Evaporite worth anything?
Entry-level Evaporite 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 Evaporite?
Evaporite is most often white, clear, pink, and gray. Color varies with impurities and locality, so confirm with hardness and luster rather than color alone.
