Granitic Pegmatite (River Rock specimen)
Granite / Pegmatite (composed of SiO2, KAlSi3O8, and NaAlSi3O8)
Category
Browse sedimentary rock (specifically a clastic sedimentary rock formed into a cobble) specimens identified by the Rock Identifier community.
Granitic Pegmatite (River Rock specimen)
Granite / Pegmatite (composed of SiO2, KAlSi3O8, and NaAlSi3O8)
Basalt with Vesicle/Vug
Basalt (Aphanitic Mafic Igneous Rock)
Basalt River Stone
Basalt (Aphanitic Mafic Igneous Rock)
Dalmatian Jasper
Dalmatian Stone (a microcrystalline quartz and feldspar rock with arfvedsonite)
Quartzite
Quartzite (primarily SiO2)
Limestone
Calcareous sedimentary rock (CaCO3)
Pink Stained Rock (Likely Quartzite or Sandstone with Iron Oxide Staining)
Quartzite (metamorphic) or Sandstone (sedimentary); coloration likely due to hematite or other iron oxides.
Pink Granite
Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)
Muscovite Mica
Muscovite / KAl2(AlSi3O10)(OH)2
Feldspar-rich Granite (Pink Granite)
Phaneritic Felsic Igneous Rock
Quartzite
Quartzite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Granodiorite Pebble
Granodiorite (containing Quartz, Plagioclase Feldspar, and Biotite/Amphibole)
Terrazzo (with Marble and Granite fragments)
Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates
Limestone (Weathered Aggregate)
Sedimentary Carbonate Rock (CaCO3)
Ocean Jasper (Orbicular Jasper)
Silicon Dioxide (SiO2)
Yellow Quartzite River Stone
Quartzite (primarily SiO2)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Quartzite (River Cobble)
Metamorphic Rock (composed predominantly of SiO2)
Shale
Shale
Sandstone
Arenite (SiO2 based)
Chert (Chalcedony/Flint)
Silicon Dioxide (SiO2)
Pink Granite (River Pebble)
Felsic Intrusive Igneous Rock
Quartzite (Yellow/Tan Quartz Cobble)
Metamorphosed Quartz Sandstone (SiO2)
Chert (Green variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Granite Cobble
Felsic intrusive igneous rock (composition: SiO₂ with KAlSi₃O₈, NaAlSi₃O₈, and CaAl₂Si₂O₈)
Chert (Jasper/Flint Pebble)
Microcrystalline quartz (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Druzy Quartz
Silicon Dioxide (SiO2)
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Granite
Granite (Felsic Intrusive Igneous Rock)
Basalt River Stone
Basalt (Aphanitic Mafic Volcanic Rock)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)
Quartz Druzy Geode
Silicon Dioxide (SiO2) - Crystalline Variety
Basalt with Epidote Veining
Basalt (Mafic Extrusive Rock) with Ca2(Al,Fe)3(SiO4)3(OH)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Satin Spar (Selenite)
Gypsum (CaSO4·2H2O)
Fossil Crab
Decapoda (likely Avitelmessus or Raninidae family)
Quartz (Milky/Common Quartz)
Silicon Dioxide (SiO2)
Hematite
Iron(III) oxide (Fe2O3)
Chert / River Pebble
Silicon Dioxide (SiO2)