Rock Identifier

Category

Organic (Paper And Cellulose)

Browse organic (paper and cellulose) specimens identified by the Rock Identifier community.

Peach Moonstone (Potassium Aluminum Silicate (KAlSi3O8); variety of Orthoclase Feldspar) — mineral

Peach Moonstone

Potassium Aluminum Silicate (KAlSi3O8); variety of Orthoclase Feldspar

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Tree Agate (Dendritic Agate (Silicon Dioxide, SiO2 + Manganese/Iron oxides)) — mineral

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2 + Manganese/Iron oxides)

Sandstone (Arenite (Sedimentary rock composed of sand-sized minerals or rock grains)) — sedimentary

Sandstone

Arenite (Sedimentary rock composed of sand-sized minerals or rock grains)

Siltstone with iron staining (Siltstone (primarily SiO2 with FeO(OH) coatings)) — sedimentary

Siltstone with iron staining

Siltstone (primarily SiO2 with FeO(OH) coatings)

Sandstone (likely Arkose) (Arenite (composed mainly of SiO2 with Feldspar)) — sedimentary

Sandstone (likely Arkose)

Arenite (composed mainly of SiO2 with Feldspar)

Chert (and Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Flint)

Silicon Dioxide (SiO2)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Garnet (Garnet Group (Silicate mineral); general formula X3Y2(SiO4)3) — mineral

Garnet

Garnet Group (Silicate mineral); general formula X3Y2(SiO4)3

Red Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Quartz (SiO2)

Milky Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Limestone (Fossiliferous) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Fossiliferous)

Calcium Carbonate (CaCO3)

Glauconitic Sandstone (Greensand (Glauconite-bearing sandstone)) — sedimentary

Glauconitic Sandstone

Greensand (Glauconite-bearing sandstone)

Pyrite in Matrix (often with Chalcopyrite) (Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)) — mineral

Pyrite in Matrix (often with Chalcopyrite)

Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Fossiliferous) (Arenite / Clastic Sedimentary Rock) — sedimentary

Sandstone (Fossiliferous)

Arenite / Clastic Sedimentary Rock

Quartzite (Metamorphosed Sandstone (mainly SiO2)) — metamorphic

Quartzite

Metamorphosed Sandstone (mainly SiO2)

Fossilized Coral (Petoskey Stone / Favosites) (Favosites (extinct genus of tabulate coral)) — sedimentary

Fossilized Coral (Petoskey Stone / Favosites)

Favosites (extinct genus of tabulate coral)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Granite Pebble (River Rock) (Granite (composed primarily of Quartz, Feldspar, and Mica)) — igneous

Granite Pebble (River Rock)

Granite (composed primarily of Quartz, Feldspar, and Mica)

Gold in Matrix (Native Gold (Au)) — mineral

Gold in Matrix

Native Gold (Au)

Quartzite Pebble (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Greenstone / Quartzite Pebble (Metamorphosed Quartz-rich Rock) — metamorphic

Greenstone / Quartzite Pebble

Metamorphosed Quartz-rich Rock

Chert (Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Quartz (SiO2)

Rose Quartz (or Quartzite) (Silicon Dioxide (SiO2)) — mineral

Rose Quartz (or Quartzite)

Silicon Dioxide (SiO2)

Milky Quartz (Crystalline Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Yellow Quartz (Chalcedony/Citrine Pebble) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Chalcedony/Citrine Pebble)

Silicon Dioxide (SiO2)

Ammonite Fossil (Ammonitida (Extinct subclass of Cephalopoda)) — sedimentary

Ammonite Fossil

Ammonitida (Extinct subclass of Cephalopoda)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Carnelian Agate (Carnelian (Silicon Dioxide: SiO2)) — mineral

Carnelian Agate

Carnelian (Silicon Dioxide: SiO2)

Coquina (Bioclastic Limestone) — sedimentary

Coquina

Bioclastic Limestone

Botryoidal Agate / Chalcedony Geode (Silicon Dioxide (SiO2)) — mineral

Botryoidal Agate / Chalcedony Geode

Silicon Dioxide (SiO2)

Yellow Aventurine (Quartz (SiO2) with iron-bearing inclusions) — mineral

Yellow Aventurine

Quartz (SiO2) with iron-bearing inclusions

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Agate)

Silicon Dioxide (SiO2)

Rose Quartz (SiO2 (Silicon Dioxide with trace inclusions of dumortierite)) — mineral

Rose Quartz

SiO2 (Silicon Dioxide with trace inclusions of dumortierite)

Limestone Pebble (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone Pebble

Sedimentary Calcium Carbonate (CaCO3)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)