igneous
Granite (Orthoclase rich)
Granite (composed primarily of Quartz and Potassium Feldspar KAlSi3O8)
Hardness: 6-7 (Mohs scale); Color: Pinkish-orange with green/grey hints; Luster: Vitreous to pearly; Crystal structure: Phaneritic (coarse-grained) igneous; Cleavage: Two directions at 90 degrees (for feldspar component); Specific gravity: 2.63 - 2.75
- Hardness
- 6-7 (Mohs scale)
- Color
- Pinkish-orange with green/grey hints
- Luster
- Vitreous to pearly
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (Mohs scale); Color: Pinkish-orange with green/grey hints; Luster: Vitreous to pearly; Crystal structure: Phaneritic (coarse-grained) igneous; Cleavage: Two directions at 90 degrees (for feldspar component); Specific gravity: 2.63 - 2.75
Formation & geological history
Formed from the slow crystallization of magma below Earth's surface. This intrusive process allows for the growth of visible mineral crystals. Most granites formed during the Phanerozoic and Proterozoic eons.
Uses & applications
Used extensively in construction for countertops, floor tiles, paving stone, curbing, and monuments. Also a primary source for mineral specimens for students and collectors.
Geological facts
Granite constitutes a large part of the continental crust. The pink color in this specimen is specifically due to a high concentration of orthoclase, a potassium-rich feldspar.
Field identification & locations
Identify in the field by its speckled, coarse appearance and its inability to be scratched by a steel knife. It is common in mountain ranges and shields like the Canadian Shield or the Appalachians.
