metamorphic
Quartz-rich metamorphic rock, likely milky quartz or quartzite
Quartz (SiO₂); possibly quartzite composed predominantly of recrystallized quartz
AI-generated identification · may be incorrectGray-white, translucent to opaque, with a glassy to dull luster and irregular fracture; quartz hardness is about 7 Mohs, with no cleavage. The granular, massive texture and possible rusty staining suggest iron-oxide inclusions or weathering.
Identified More metamorphic →
Explore Quartz-rich metamorphic rock, likely milky quartz or quartzite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Gray-white, translucent to opaque, with a glassy to dull luster and irregular fracture; quartz hardness is about 7 Mohs, with no cleavage. The granular, massive texture and possible rusty staining suggest iron-oxide inclusions or weathering.
Formation & geological history
If quartzite, it formed when quartz-rich sandstone was compressed and recrystallized during metamorphism, commonly during Precambrian to Paleozoic mountain-building. If a quartz vein fragment, it precipitated from silica-rich hydrothermal fluids in fractures.
Uses & applications
Common quartzite is used as aggregate, landscaping stone, and durable building material; clear quartz may be collected or used ornamentally. This irregular specimen has little commercial value unless it displays unusual crystals or inclusions.
Geological facts
Quartz is one of Earth’s most abundant minerals and is chemically silicon dioxide. Its lack of cleavage and ability to scratch glass are useful diagnostic traits.
Field identification & locations
Look for a white or gray, very hard, glassy material that scratches ordinary glass and does not react with dilute acid. Common worldwide, especially in quartz veins and metamorphic belts; approximate value is $1–$10 for a hand specimen, potentially higher if crystal-rich.
More like this
