metamorphic
Tumbled quartz-rich pebble, likely quartzite or chert
Quartz (SiO₂), possibly quartzite; exact identification is uncertain from the image
AI-generated identification · may be incorrectHardness about 7 Mohs, tan to honey-brown, translucent in thin areas, with a waxy to dull luster and no obvious cleavage. Rounded edges and surface polish indicate tumbling; visible pale patches may be quartz or weathering zones.
Identified More metamorphic →
Explore Tumbled quartz-rich pebble, likely quartzite or chert in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness about 7 Mohs, tan to honey-brown, translucent in thin areas, with a waxy to dull luster and no obvious cleavage. Rounded edges and surface polish indicate tumbling; visible pale patches may be quartz or weathering zones.
Formation & geological history
Quartzite forms when quartz-rich sandstone recrystallizes under heat and pressure; chert forms by silica precipitation or replacement in sedimentary environments. The specimen’s geological age and precise origin cannot be determined visually.
Uses & applications
Used as a decorative tumbled stone, craft material, and collector specimen; quartzite is also used as aggregate and building stone. Typical value is modest unless unusually attractive or proven to be a rare variety.
Geological facts
Its strong resistance to scratching is characteristic of quartz-rich material. A steel file should not scratch it; glass-scratching ability would support a quartz identification.
Field identification & locations
Commonly found in stream gravels and metamorphic or sedimentary terrains worldwide. Distinguish it from calcite by hardness: calcite scratches easily with a knife and fizzes in dilute hydrochloric acid.
More like this
