Properties
| Category | Tectosilicate minerals |
|---|---|
| Formula | KAlSi3O8 |
| Crystal system | Triclinic |
| Color | White, grey, greyish yellow, yellowish, tan, salmon-pink, bluish green, green. |
| Crystal habit | Can be anhedral or euhedral. Grains are commonly elongate with a tabular appearance. May contain lamellae which formed from exsolved albite. |
| Cleavage | Has perfect cleavage parallel to {001} and good cleavage on {010}. Cleavages intersect at 90°41'. It can be difficult to see cleavage in thin section due to microcline's low relief. |
| Fracture | Uneven |
| Tenacity | Brittle |
| Mohs scale hardness | 6–6.5 |
| Luster | Vitreous |
| Streak | White |
| Diaphaneity | Transparent, translucent |
| Specific gravity | 2.5–2.6 |
From the Wikipedia article
Microcline (KAlSi3O8) is an important igneous rock-forming tectosilicate mineral. It is a potassium-rich alkali feldspar. It is common in granite and pegmatites. Microcline forms during slow cooling of orthoclase. Sanidine is a polymorph of alkali feldspar stable at yet higher temperature. Microcline has cross-hatch twinning that forms as a result of the transformation of monoclinic orthoclase into triclinic microcline.
Source
Source record: crystal-compendium/microcline/minerals.json. Fetched from English Wikipedia by the operator 2 October 2026.
https://en.wikipedia.org/wiki/Microcline — revision id 1339920347. Text and properties from Wikipedia, licensed CC BY-SA 4.0.