Quartzite Pebble
Quartzite (primarily SiO2)
Category
Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.
Quartzite Pebble
Quartzite (primarily SiO2)
Quartzite
Quartzite (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Siltstone
Siltstone
Schist
Mica Schist (primarily composed of quartz, feldspar, and mica)
Blue Celestite (Celestine)
Strontium sulfate (SrSO4)
Chert (often colloquially called Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert Concretion with Iron Oxide Staining
Microcrystalline Quartz (SiO2)
Corundum
Corundum (Al2O3)
Chert / Flint
Silicon Dioxide (SiO2)
Serpentine
Serpentine (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Chert (with Quartz Veining)
Microcrystalline Quartz (SiO2)
Quartz / Common Gravel
Silicon Dioxide (SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Limestone
Calcite rock (CaCO3)
Fossiliferous Limestone
Bioclastic Limestone (Calcium Carbonate, CaCO3)
Chert (Flint)
Cryptocrystalline Silica (SiO2)
Crushed Limestone
Limestone (CaCO3)
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chert (Nodule)
Chert (Cryptocrystalline Silica, SiO2)
Coquina
Bioclastic Limestone
Coquina
Biogenic Limestone (CaCO3)
Chert / River Cobble
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Blue Apatite
Fluorapatite - Ca5(PO4)3F
Limestone
Calcium Carbonate (CaCO3)
Raw emerald-bearing beryl (probable)
Beryl, Be₃Al₂Si₆O₁₈; green color from trace chromium and/or vanadium
Tree Agate
Silicon dioxide (SiO2)
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Muscovite Mica (with Quartz matrix)
Muscovite - KAl2(AlSi3O10)(OH)2
Puddingstone
Conglomerate
Fuchsite (Chrome Mica)
Cr-bearing Muscovite - K(Al,Cr)2(AlSi3O10)(OH)2
Citrine
Citrine (Silicon Dioxide - SiO2)
Sandstone (Weathered Pebble)
Arenite (composed primarily of SiO2)
Aura Quartz Geodes (Lab-Altered)
Silicon Dioxide (SiO2) with Metallic Vapor Deposition
Siltstone
Siltstone (clastic sedimentary rock)
Mica Schist
Mica Schist
Schist
Mica Schist (Group of medium-grade metamorphic rocks)
Mica Schist
Mica Schist (predominantly composed of Muscovite or Biotite silicates)
Schist (Micaceous)
Mica Schist
Schist
Mica Schist
Mica Schist
Crystalline Schist (often primarily Muscovite or Biotite sheet silicates)