metamorphic
Likely quartz-rich metamorphic rock (quartzite)
Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with feldspar or mica impurities
AI-generated identification · may be incorrectGray-white, massive and fine-to-medium granular, with a sugary/vitreous luster and no obvious cleavage; quartz hardness is about 7 Mohs, and specific gravity is approximately 2.65. The elongated piece appears naturally weathered or possibly shaped, but lighting limits certainty.
Identified More metamorphic →
Explore Likely quartz-rich metamorphic rock (quartzite) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Gray-white, massive and fine-to-medium granular, with a sugary/vitreous luster and no obvious cleavage; quartz hardness is about 7 Mohs, and specific gravity is approximately 2.65. The elongated piece appears naturally weathered or possibly shaped, but lighting limits certainty.
Formation & geological history
Forms when quartz-rich sandstone is recrystallized under elevated temperature and pressure during regional metamorphism; ages range from Precambrian to younger depending on the source terrane. Common in mountain belts and resistant ridges.
Uses & applications
Used as crushed aggregate, road stone, decorative facing, and occasionally carving or lapidary material. This specimen has modest value unless its locality, texture, or unusual shape is documented.
Geological facts
Quartzite commonly breaks across grains rather than around them, unlike sandstone, and can be harder than a steel knife. Its pale color reflects abundant quartz, while gray tones usually indicate mica, iron oxides, or other impurities.
Field identification & locations
Field identification: it should scratch ordinary glass and resist a steel blade; freshly broken surfaces look granular and lack visible sand grains or bedding. Common worldwide, especially in metamorphic mountain regions.
More like this
