Shale
Fissile mudrock (composed primarily of clay minerals and quartz)
Category
Browse sedimentary rock (altered) specimens identified by the Rock Identifier community.
Shale
Fissile mudrock (composed primarily of clay minerals and quartz)
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
Sandstone
Quartz Sandstone (predominantly)
Chert (Agatized/Chalcedony variety)
Microcrystalline Quartz (SiO2)
Metaconglomerate
Metaconglomerate (Quartzite conglomerate)
Sandstone or Limestone
Sedimentary Rock
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
River Rock / Stream Pebble
Fluvial Clast / Rounded Sedimentary Particle
Sandstone
Arenite (SiO2 dominant)
Citrine Quartz
Citrine (Silicon Dioxide - SiO2)
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Unakite
Unakite (Altered Granite composed of Orthoclase KAlSi3O8, Epidote Ca2(Al, Fe)3(SiO4)3(OH), and Quartz SiO2)
Sandstone (Painted)
Arenite (primarily SiO2)
Sandstone with Quarzite clasts
Arenite (SiO2 based)
Mudstone
Lutylite (group of fine-grained sedimentary rocks)
Slate
Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
Unakite
Unakite (Altered Granite consisting of Orthoclase KAlSi3O8, Epidote Ca2(Al,Fe)3(SiO4)3(OH), and Quartz SiO2)
Sandstone (Ferruginous)
Arenite (Siliclastic Sedimentary Rock)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone (Weathered Cobble)
Clastic sedimentary rock (primarily SiO2)
Quartz Geode (likely within Limestone or Dolomite matrix)
Quartz (SiO₂)
Red Jasper
Jasper (a variety of Chalcedony, SiO₂ with impurities)
Sandstone
Sandstone (clastic sedimentary rock)
Conglomerate
Conglomerate (Detrital Sedimentary Rock)
Lapis Lazuli
A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).
Shale
Shale (Consolidated fine-grained clay/silt)
Sandstone (with potentially high Feldspar/Arkose content)
Clastic sedimentary rock (SiO2 dominated)
Chert (Yellow/Tan Variety)
Chert (SiO2)
Amber-bearing Coal/Sedimentary Rock
Bituminous coal or carbonaceous siltstone with Fossilized Tree Resin (C10H16O)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Geode with Quartz and possibly Jasper/Hematite
Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides
Gastropod Steinkern (Internal Mold Fossil)
Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix
Turquoise
Turquoise (Hydrated copper aluminum phosphate, CuAl6(PO4)4(OH)8·4H2O)
Herkimer Diamond
Quartz (Silica - SiO2)
Pyrite in Shale
Iron Disulfide (FeS2)
Sandstone or Limestone
Arenite or Calcareous Sedimentary Rock
Quartzite (Yellow/Orange variety)
Quartzite (primarily SiO2)
Sandstone (Ferruginous)
Arenite with Iron Oxide (Limonite/Hematite) coating