Properties
| Category | Tectosilicate minerals |
|---|---|
| Formula | (Ca,Na)(Al,Si)4O8 (Na:Ca = 30:70 to 50:50) |
| Crystal system | Triclinic |
| Color | Gray, gray-white, or colorless with blue, pale green, or brown iridescence ; Spectrolite: may display pink, orange, or purple iridescence |
| Crystal habit | Crystals typically thin and tabular, rhombic in cross section, striated; massive |
| Cleavage | Perfect on {001}, less perfect on {010}, intersecting at near 90°; distinct on {110} |
| Fracture | Uneven to conchoidal |
| Mohs scale hardness | 6–6.5 |
| Luster | Vitreous to pearly on cleavages |
| Streak | White |
| Diaphaneity | Translucent to transparent |
| Specific gravity | 2.68 to 2.72 |
From the Wikipedia article
Labradorite ((Ca, Na)(Al, Si)4O8) is a calcium-enriched feldspar mineral first identified in Labrador, Canada, which can display an iridescent effect (schiller).
Source
Source record: crystal-compendium/labradorite/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Labradorite — revision id 1364496330. Text and properties from Wikipedia, licensed CC BY-SA 4.0.