Limestone
Calcium Carbonate (CaCO3)
sedimentary
Category
Industrial Byproduct (Anthropogenic Rock)
Browse industrial byproduct (anthropogenic rock) specimens identified by the Rock Identifier community.
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Limestone
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Likely milky quartz fragment
Quartz (silicon dioxide, SiO₂)
mineral
Basalt with Iron Oxide staining
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Limonitic Quartzite
Metamorphosed sandstone with Limonite (FeO(OH)·nH2O) staining
metamorphic
River Pebble (Gneiss/Schist mix)
Metamorphic rock aggregate
metamorphic
Basalt
Mafic Igneous Rock
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Basalt
Basalt
igneous
Tumbled unakite
Unakite: epidote, pink potassium feldspar (orthoclase), and commonly quartz
metamorphic
Clear quartz (rock crystal)
Quartz, silicon dioxide (SiO₂)
mineral
Silicon Carbide (Carborundum)
Silicon Carbide (SiC)
mineral
Red Sandstone
Sandstone (lithic arenite or arkose with iron oxide)
sedimentary
Quartzite (specifically a river-worn pebble)
Quartzite (primarily SiO2)
metamorphic
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Unidentified weathered mineral/rock fragment
Indeterminate; likely a weathered iron-rich silicate or sulfide-bearing specimen
mineral
Basalt
Basalt (Mafic Extrusive Igneous Rock)
igneous
Basalt River Stone
Basalt (Mafic volcanic rock)
igneous
Limestone (Weathered)
Sedimentary Carbonate Rock (CaCO3)
sedimentary
Reddish-brown rock fragment, possibly iron-stained sandstone
Unidentified iron-oxide-stained rock; sandstone is a tentative visual identification
sedimentary
Rounded beach or river pebble
Unidentified fine-grained rock; composition cannot be determined from the image
sedimentary
Vesicular Basalt
Extrusive mafic igneous rock (Basalt)
igneous
Basalt (Weathered)
Extrusive Igneous Rock (Mafic composition)
igneous
Tiny amber-colored crystal fragment
Indeterminate; possibly quartz, feldspar, mica, or a sulfide mineral
mineral
Likely tumbled purple quartzite or jasper
Quartz-rich rock; exact identification is uncertain from the image
metamorphic
Barite Rose
Barium Sulfate (BaSO4)
mineral
Sandstone
Arenite (SiO2 primarily)
sedimentary
Iron-stained Quartz Vein
Silicon Dioxide (SiO2) with Limonite/Hematite inclusions
mineral
Small quartz-rich rock fragment
Unidentified quartz-bearing rock; the image is insufficient for a precise identification
igneous
Artificial Rock Face (Faux Rock)
Glass Fiber Reinforced Concrete (GFRC)
man-made/construction material
Pumice
Pumice (a vesicular volcanic glass)
igneous
Peridot in Basalt
Olivine ((Mg, Fe)2SiO4) in Basalt
mineral
Small weathered rock fragments
Unidentified lithic fragments; composition cannot be determined from the image
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Limestone Riprap
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Pumice
Pumice (a vesicular volcanic glass)
igneous
Basalt
Basalt (Mafic volcanic rock)
igneous
Blue slag glass / industrial glass fragment
Artificial silicate glass, composition variable; likely copper- or cobalt-colored furnace slag
mineral
Small pale rock fragment
Indeterminate; possibly quartz, calcite, or a weathered feldspar-rich fragment
mineral