RocksdayAlbite vs Microcline
To tell Albite from Microcline: Albite is the sodium feldspar, usually whiter, with fine striations.
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
The common potassium feldspar of granite pegmatites. Green microcline is amazonite. By eye it looks like orthoclase.
Photo: Robert M. Lavinsky, CC BY-SA 3.0
Key differences
- Albite is the sodium feldspar, usually whiter, with fine striations.
Side by side
| Property | Albite | Microcline |
|---|---|---|
| Type | Mineral | Mineral |
| Mohs hardness | 6–6.5 | 6–6.5 |
| Luster | Vitreous to pearly | Vitreous to pearly |
| Streak | White | White |
| Colors | White, Clear | Pink, White, Green, Gray |
| Crystal system | Triclinic | Triclinic |
| Specific gravity | 2.6–2.65 | 2.54–2.63 |
| Formula | NaAlSi₃O₈ | KAlSi₃O₈ |
| Found in | Minas Gerais, Brazil; Gilgit-Baltistan, Pakistan | Pegmatites in Colorado; Minas Gerais, Brazil |
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 microcline
- Blocky pink, white or green crystals with two cleavages near 90°.
- Hardness about 6 — scratches glass with difficulty.
- Green pieces are amazonite. Pink and white ones cannot be separated from orthoclase without a microscope.
Crystal system: Triclinic
Full Microcline guide →More comparisons
Frequently asked questions
What is the difference between albite and microcline?
Albite is a mineral (NaAlSi₃O₈) with a Mohs hardness of 6–6.5 and a vitreous to pearly luster, usually white or colorless. Microcline is a mineral (KAlSi₃O₈) with a Mohs hardness of 6–6.5 and a vitreous to pearly luster, usually pink, white, green or gray.
How can you tell albite from microcline?
Albite is the sodium feldspar, usually whiter, with fine striations.
Could you tell them apart from a blurry close-up?
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