Weathered granite or granitic pegmatite
Coarse-grained quartz–feldspar–mica rock; likely granite, possibly pegmatitic granite
igneous
Category
Sedimentary Rock (Possibly Composed Of Various Minerals)
Browse sedimentary rock (possibly composed of various minerals) specimens identified by the Rock Identifier community.
Learn about Sedimentary Rock (Possibly Composed Of Various Minerals) in the encyclopedia
View all →
Quartz
Silicon Dioxide (SiO2)
mineral
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Feldspar, and Mica)
igneous
Granite
Granite (a common rock type, not a single mineral species)
Igneous
Granite with Mafic Inclusions
Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)
igneous
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Quartz (Clear/Milky)
Silicon Dioxide (SiO2)
mineral
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Yellow Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz pebble or seed/crumb
SiO2 (if quartz)
mineral
Limestone
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Jasper
Microcrystalline quartz (SiO2)
sedimentary
Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Granite (Dioritic variant)
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Granite
Phaneritic felsic intrusive igneous rock
igneous
Shark Tooth Fossil
Lamniformes (Shark tooth fossil composed of Fluorapatite)
fossil
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Likely slag or metallic industrial byproduct
Unidentified iron-rich ferrous slag; possibly magnetite-bearing slag
mineral
Weathered fossiliferous limestone fragment, possibly fossil coral or shell material
Indeterminate carbonate fossil in calcitic limestone; likely composed mainly of calcite (CaCO₃), but species identification is not possible from this image alone
fossil
Weathered volcanic rock, likely basalt
Basalt; commonly composed of plagioclase, pyroxene, and iron-rich oxides
igneous
Gneiss (Metamorphosed Granitic Rock)
Gneiss (composed mainly of quartz, feldspar, biotite, and/or hornblende)
metamorphic
Banded Sandstone
Arenite (composed primarily of Quartz: SiO2)
sedimentary
Jasper (Polychrome Jasper)
Silicon Dioxide (SiO2) with various inclusions
sedimentary
Granite
Phaneritic Plutonic Rock (Granite)
igneous
Chert (Flint) Artifact
Silicon Dioxide (SiO2)
sedimentary
Polished orbicular stone, likely granite or diorite
Granite–diorite, composed mainly of feldspar, quartz, and dark amphibole/biotite
igneous
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcite, CaCO3)
sedimentary
Chert (Flint)
Chert (SiO2)
sedimentary
Cobblestones (Basalt/River Rock)
Polished lithic fragments and rounded pebbles
sedimentary
Quartzite Cobble
Quartzite (composed primarily of SiO2)
metamorphic
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Druzy quartz geode
Microcrystalline quartz (SiO₂), commonly lining a volcanic geode cavity
mineral
Quartz-rich rock, likely milky quartz vein material
Quartz (SiO₂), possibly iron-stained massive quartz with minor feldspar or mica
mineral
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Mineral
Fossilized Shark Tooth (Otodus obliquus)
Otodus obliquus (composed primarily of Fluorapatite)
mineral
Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Chert (specifically Jasper/Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Olivine Weathered Rock (Dunite)
Dunite ((Mg, Fe)2SiO4)
igneous
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Gneiss
Gneiss (Metamorphic Rock)
metamorphic
Siltstone Pebble
Siltstone (composed of siliciclastic grains)
sedimentary