RocksdayAlbite vs Amblygonite
How to tell them apart
The sodium-rich plagioclase feldspar. In pegmatites it forms white platy crystals that often host tourmaline and other gems.
Photo: Rock Currier, CC BY 3.0
A lithium aluminum phosphate from pegmatites, usually white and blocky.
Photo: Luis Miguel Bugallo Sánchez (Lmbuga Commons)(Lmbuga Galipedia) Publicada por/Publish by: Luis Miguel Bugallo Sánchez, CC BY-SA 3.0
Key differences
- Albite is lighter and shows fine striations.
Side by side
| Property | Albite | Amblygonite |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6–6.5 | 5.5–6 |
| Luster | Vitreous to pearly | Vitreous to greasy |
| Streak | White | White |
| Colors | White, Clear | White, Yellow, Green |
| Crystal system | Triclinic | Triclinic |
| Specific gravity | 2.6–2.65 | 3–3.1 |
| Formula | NaAlSi₃O₈ | (Li,Na)AlPO₄(F,OH) |
| Found in | Minas Gerais, Brazil; Gilgit-Baltistan, Pakistan | Minas Gerais, Brazil; Maine |
Properties that are the same for both are grayed out.
How to identify albite
- White, platy or bladed crystals.
- Fine parallel striations on cleavage faces.
- Hardness about 6.
Crystal system: Triclinic
Full Albite guide →How to identify amblygonite
- White to pale yellow blocky masses.
- Looks like feldspar but is heavier.
- Hardness about 6.
Crystal system: Triclinic
Full Amblygonite guide →More comparisons
Could you tell them apart from a blurry close-up?
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