Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Category
Browse igneous or sedimentary (water worn) specimens identified by the Rock Identifier community.
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Siltstone
Siltstone (composed of microscopic silt-sized particles of quartz and feldspar)
Aquamarine
Beryl (Be3Al2Si6O18)
Ferruginous Conglomerate
Ferruginous Conglomerate (Clastic Sedimentary Rock)
Amber / Copal
Succinite (fossilized tree resin)
Basalt with Quartz Vein
Basalt (Mafic volcanic rock) with secondary Quartz (SiO2) intrusion
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Granitic Pegmatite
Pegmatitic Granite
Pegmatitic Granite
Granite with Orthoclase Feldspar and Quartz (SiO2, KAlSi3O8)
Basalt River Pebble
Aphanitic Mafic Basalt
Granite featuring Quartz Vein
Granite with hydrothermal silica (SiO2) intrusion
Jasper and Agate
Microcrystalline Quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Dalmatian Stone
Dalmatian Jasper (Peralkaline Quartz-Feldspar Rock)
Limonitic Scoria (Vesicular Basalt with Iron Staining)
Highly vesicular basalt heavily stained by Limonite [FeO(OH)·nH2O]
Quartz Geode
Silicon Dioxide (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Chalcedony
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Hematite
Iron(III) oxide (Fe2O3)
Hematite
Iron(III) oxide (Fe2O3)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Pink Chalcedony (Agate/Jasper blend)
Silicon Dioxide (SiO₂)
Chalk
Calcium Carbonate (CaCO3)
Devil's Toenail (Fossil Oyster)
Gryphaea arcuata (Calcium Carbonate, CaCO3)
Moqui Marble (Ironstone Concretion)
Goethite/Hematite Concretion (Fe2O3 / FeO(OH))
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
Breccia
Breccia
Limestone
Calcareous sedimentary rock (primarily CaCO3)
Limonite (Ironstone Concretion)
Limonite (Hydrous ferric oxide mixture, FeO(OH)·nH2O)
Conglomerate
Conglomerate (Sedimentary Clastic Rock)
Limestone
Calcium Carbonate (CaCO3)
Sandstone (with Iron Staining)
Clastic sedimentary rock (SiO2 with Fe2O3 impurities)
River Pebble (Quartz-rich)
Silicon Dioxide (SiO2) with various inclusions
Banded Calcite (Cave Onyx)
Calcium Carbonate (CaCO3)
Chert (often called Jasper or River Siltstone)
Chert (SiO2)
Scoria (Vesicular Basalt)
Scoria (Extrusive Igneous Rock)
Limestone
Calcium Carbonate (CaCO3)
River Rock (River Cobbles)
Fluvial Conglomerate Clasts (primarily composed of various minerals such as Quartz, SiO2)
Silver Sheen Obsidian
Volcanic Glass (Amorphous Silicon Dioxide - SiO2 with impurities)
Pink Granite
Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)
Granitic Pegmatite with Schorl Tourmaline
Granitic Pegmatite (Schorl: NaFe3Al6(BO3)3Si6O18(OH)4)
Pegmatite
Granitic Pegmatite