Unakite
Epidotized Granite (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))
Category
Browse not a rock (man made polymer) specimens identified by the Rock Identifier community.
Unakite
Epidotized Granite (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, Mg3Si2O5(OH)4)
Crinaudite / Fossilized Crinoid Stem
Crinoid (Echinodermata) in a Calcitic/Siliceous Matrix
Unakite
Epidotized Granite
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Quartzite with Quartz Veining
Quartzite (primarily SiO2)
Peridot (Olivine)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
Fossilized Gastropod (Snail)
Class Gastropoda (internal mold or 'steinkern')
Sandstone
Arenite (composed primarily of SiO2)
White Precious Opal
Hydrated Silica (SiO2·nH2O)
Chert (specifically Yellow or River Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Rhyolite
Rhyolite (High-silica volcanic rock)
Sandstone (Pebble)
Arenite (primarily SiO2)
Garnet Schist
Almandine-Garnet Mica Schist
Limestone
Calcium Carbonate (CaCO3)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (CaCO3)
Peridotite
Ultramafic intrusive rock (Peridotite)
Dalmation Stone
Peralkaline Rock (SiO2 with Arfvedsonite)
Sandstone (Fossiliferous)
Arenite / Clastic Sedimentary Rock
Basalt (Road Aggregate / Crushed Stone)
Aphanitic Mafic Igneous Rock
Basalt
Extrusive Mafic Igneous Rock
Granite
Phaneritic Felsic Intrusive Rock
Granite
Felsic Plutonic Rock (Granite)
Sandstone
Arenite (SiO2 primarily)
Scoria (Lava Rock)
Scoria
Red Sandstone (Arkose)
Clastic Sedimentary Rock (Lithic Arkose)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Epidote in Matrix (Unakite-related)
Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))
Sandstone
Clastic Sedimentary Rock (composed mostly of quartz, SiO2)
Chert (Chert / Flint)
Silicon dioxide (SiO2) - Microcrystalline quartz
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Milky Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2
Quartzite
Quartzite (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Orthoceras Fossil in Limestone
Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone
Chert (Nodule)
Silicon Dioxide (SiO2)
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Quartzite Pebble
Quartzite (SiO2 with minor impurities)
Green Porphyry (Flowerstone)
Porphyritic Andesite or Basalt
Charoite
Charoite (Hydrated potassium sodium calcium barium strontium silicate hydroxyfluoride)