metamorphic
Rounded iron-stained quartzite or sandstone pebble
Quartzite, predominantly SiO₂, with iron-oxide staining
AI-generated identification · may be incorrectHardness about 7 Mohs; tan to orange-brown, fine-grained, matte to slightly vitreous luster, and no visible cleavage. The smooth shape indicates water abrasion or tumbling; pale patches may be quartz-rich areas or surface weathering.
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Physical properties
Hardness about 7 Mohs; tan to orange-brown, fine-grained, matte to slightly vitreous luster, and no visible cleavage. The smooth shape indicates water abrasion or tumbling; pale patches may be quartz-rich areas or surface weathering.
Formation & geological history
Likely a naturally rounded river or beach cobble derived from quartz-rich sandstone metamorphosed into quartzite; exact age and locality cannot be determined from the photograph. Iron oxides formed or accumulated during weathering, producing the orange coloration.
Uses & applications
Commonly collected as a decorative stone, worry stone, or craft material; quartzite is also used as aggregate, building stone, and durable paving material.
Geological facts
Quartzite resists scratching by ordinary steel and is generally tougher than sandstone because quartz grains are tightly recrystallized and interlocked.
Field identification & locations
Look for a sugary crystalline texture and grains that break through rather than crumble; sandstone usually shows more obvious loose grains and is softer. Common in stream gravels and glacial deposits worldwide.
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