Granite Pebble
Felsic intrusive igneous rock
Category
Browse sedimentary or igneous specimens identified by the Rock Identifier community.
Granite Pebble
Felsic intrusive igneous rock
Sodalite
Na8(Al6Si6O24)Cl2
Granite (likely a river or beach pebble)
Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Pegmatite
Granitic Pegmatite
Amethyst
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Corundum (Sapphire in Host Rock)
Corundum (Aluminum Oxide, Al2O3)
Limonite (Ironstone Concretion)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
Granite (Weathered River Rock)
Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Diorite (or salt-and-pepper granite pebble)
Phaneritic Igneous Rock (Intermediate Composition)
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Blue Apatite
Apatite-(CaF), Ca5(PO4)3F (Calcium Fluorophosphate)
Yellow Agate
Silicon Dioxide (SiO2)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Hypersthene
Hypersthene (Magnesium Iron Silicate - (Mg,Fe)SiO3)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Sodalite
Na8(Al6Si6O24)Cl2
Quartz with Muscovite Mica
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)
Sandstone (Quartzite-rich Cobble)
Clastic sedimentary rock (primarily SiO2)
Labradorite (Larvikite variety)
(Na,Ca)(Al,Si)4O8 (Plagioclase Feldspar)
Granite
Granite (Phaneritic intrusive igneous rock)
Snowflake Obsidian
Volcanic glass containing Spherulite inclusions (primarily Cristobalite, SiO2)
Labradorite (likely Black Labradorite or Larvikite)
Labradorite (Na,Ca)(Al,Si)4O8. If a rock, it is typically anorthosite, gabbro, or norite, or a variety of syenite called Larvikite if it is specifically from Larvik, Norway.
Arfvedsonite in Quartz (also known as Eudialyte/Garnet Syenite variety)
Arfvedsonite [Na3(Fe2+)4Fe3+Si8O22(OH)2] within a silicate matrix
Porphyritic Basalt (likely Chinese Writing Stone)
Porphyritic Basalt / Plagioclase Feldspar in Basal Matrix
Olivine Diabase Porphyry
Porphyritic Olivine-Bearing Diabase (Micro-Gabbro)
Granite Cobble
Granite (Felsic Intrusive)
Fossilized Fish Skeleton in Matrix
Vertebrata (Class: Actinopterygii), typically found in limestone or shale matrices
Granite
Phaneritic Plutonic Felsic Rock (major components: SiO2 and Al2O3)
Granite
Granite
Jasper
Silicon dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Geode (Unopened)
Silica-rich concretion (SiO2)
Jasper and Ironstone (likely Jasperized Ironstone)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Granite
Granite (Felsic Plutonic Rock)
Snowflake Obsidian
Volcanic glass (SiO2) with Cristobalite (SiO2) inclusions
Granite (Pink/Red)
Phaneritic Plutonic Felsic Rock (major minerals: Quartz, Orthoclase Feldspar, Plagioclase Feldspar)
Granite
Granite (Felsic intrusive igneous rock)
Granite
Granite (Felsic Plutonic Rock)