Rock Identifier

Category

Organic (Often Found By Beachcombers)

Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.

Lepidolite on Pegmatite (Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)) — mineral

Lepidolite on Pegmatite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Sodalite (Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Na8(Al6Si6O24)Cl2

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

Quartzite (River Pebble)

Metamorphosed Quartz Sandstone (SiO2)

Quartzite (Quartzite (composed primarily of SiO2)) — metamorphic

Quartzite

Quartzite (composed primarily of SiO2)

Ruby (Corundum (Al2O3 with Chromium traces)) — mineral

Ruby

Corundum (Al2O3 with Chromium traces)

Amethyst (SiO2 (Amethyst is a variety of Quartz)) — mineral

Amethyst

SiO2 (Amethyst is a variety of Quartz)

Basalt (Vesicular) (Mafic Volcanic Rock (rich in Magnesium and Iron)) — Igneous

Basalt (Vesicular)

Mafic Volcanic Rock (rich in Magnesium and Iron)

Yellow Jasper (Silicon Dioxide (SiO2) with goethite or limonite inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with goethite or limonite inclusions

Chert (Agatized) (Silicon dioxide (SiO2)) — sedimentary

Chert (Agatized)

Silicon dioxide (SiO2)

Moqui Marble (Ironstone Concretion (Goethite/Hematite)) — sedimentary

Moqui Marble

Ironstone Concretion (Goethite/Hematite)

Fluorite (tumbled pebble) (Calcium Fluoride (CaF2)) — mineral

Fluorite (tumbled pebble)

Calcium Fluoride (CaF2)

Aventurine (Tan/Cream colored) (Quartz (SiO2) with mineral inclusions) — mineral

Aventurine (Tan/Cream colored)

Quartz (SiO2) with mineral inclusions

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Healer's Gold (Pyrite/Magnetite in Serpentine) (Magnetite (Fe3O4) and Pyrite (FeS2) in Lizardite/Antigorite [Mg3Si2O5(OH)4]) — metamorphic

Healer's Gold (Pyrite/Magnetite in Serpentine)

Magnetite (Fe3O4) and Pyrite (FeS2) in Lizardite/Antigorite [Mg3Si2O5(OH)4]

Greenstone (Greenstone River Pebble) (Greenschist (metamorphosed mafic igneous rock)) — metamorphic

Greenstone (Greenstone River Pebble)

Greenschist (metamorphosed mafic igneous rock)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Sandstone (Tumbled/River Pebble) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (Tumbled/River Pebble)

Arenite (composed primarily of SiO2)

Quartz (Milky or Cloudy variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or Cloudy variety)

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining (Silicon Dioxide (SiO2)) — mineral

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Greenstone (Greenschist / Meta-basalt) — metamorphic

Greenstone

Greenschist / Meta-basalt

Serpentinite (Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4) — metamorphic

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Slate (Foliated Metamorphic Rock) — metamorphic

Slate

Foliated Metamorphic Rock

Quartzite pebble (Quartzite (SiO2)) — metamorphic

Quartzite pebble

Quartzite (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Ruby (Corundum (Al2O3 with Chromium impurities)) — mineral

Ruby

Corundum (Al2O3 with Chromium impurities)

Granite (Phaneritic Felsic Igneous Rock) — igneous

Granite

Phaneritic Felsic Igneous Rock

Granite (Granite (comprised primarily of Quartz (SiO2), Feldspar (KAlSi3O8), and Mica (KAl2(AlSi3O10)(OH)2))) — igneous

Granite

Granite (comprised primarily of Quartz (SiO2), Feldspar (KAlSi3O8), and Mica (KAl2(AlSi3O10)(OH)2))

Granite (Phaneritic Felsic Igneous Rock (composed primarily of Quartz and Alkali Feldspar)) — igneous

Granite

Phaneritic Felsic Igneous Rock (composed primarily of Quartz and Alkali Feldspar)

Botryoidal Goethite (Goethite (α-Fe3+O(OH))) — mineral

Botryoidal Goethite

Goethite (α-Fe3+O(OH))

Sandstone (Ferruginous) (Arenite (with Iron Oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (with Iron Oxide cement)

Quartz (Massive Quartz or Quartzite) (Silicon Dioxide (SiO2)) — mineral / metamorphic

Quartz (Massive Quartz or Quartzite)

Silicon Dioxide (SiO2)

mineral / metamorphic

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Quartzite (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite

Metamorphosed Quartz Sandstone (SiO2)

Schist (specifically Mica Schist) (Mica Schist (primarily composed of Muscovite KAl2(AlSi3O10)(OH)2 and Biotite)) — metamorphic

Schist (specifically Mica Schist)

Mica Schist (primarily composed of Muscovite KAl2(AlSi3O10)(OH)2 and Biotite)

Limestone (Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Sandstone (Quartz Sandstone (predominantly)) — Sedimentary

Sandstone

Quartz Sandstone (predominantly)

Chert (White Variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (White Variety)

Silicon Dioxide (SiO2)

Chert Nodule (with Flint core) (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (with Flint core)

Sedimentary Cryptocrystalline Quartz (SiO2)

Diorite (Diorite) — igneous

Diorite

Diorite

Yellow Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Yellow Calcite

Calcite (Calcium Carbonate, CaCO3)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)