Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Category
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Quartz Geode with Calcite
Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2)
Biotite Mica
K(Mg,Fe2+)3(Al,Fe3+)Si3O10(OH,F)2
Rough Diamond
Diamond (pure Carbon, C)
Diamond
Diamond (pure Carbon, C)
Pink Feldspar
Orthoclase (KAlSi3O8) or Microcline
Rough Tanzanite
Zoisite (Ca2Al3(SiO4)3(OH))
Conglomerate
Conglomerate (clastic sedimentary rock)
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(OH)₄(BO₃)₃Si₆O₁₈)
Garnet Beads
Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)
Blue Sapphire
Corundum (Al2O3 with iron and titanium trace elements)
Gold Ore (in Quartz/Pyrite)
Native Gold (Au) with Quartz (SiO2) and Pyrite (FeS2)
Sandstone
Sandstone (lithified arenite/wacke)
Ruby in Fuchsite
Corundum (Al2O3) in Fuchsite (K(Al,Cr)3Si3O10(OH)2)
Pink Thulite (in Pumice-like texture)
Pink Zoisite (Mn-bearing Zoisite), Ca2Al3(SiO4)3(OH)
Veined Quartz
SiO2 (Silicon Dioxide)
Quartz Geode (Druzy Quartz)
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Green Kyanite
Kyanite (Al2SiO5)
Quartzite
Quartzite (SiO2)
Serpentine (Nephrite-like River Cobble)
Serpentinite (Hydrous Magnesium Iron Silicate)
Jade (Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3)
Banded Gneiss
Gneiss (pronounced "nice")
Quartz
Quartz (SiO₂)
Sandstone
Arenite
Chert (Flint)
Chert (̑SiO2)
Ferromanganese Nodule
Polymetallic Nodule (composed primarily of MnO2 and Fe2O3)
Brown Jasper (Chert)
Silicon Dioxide (SiO2)
Stalagmite (Flowstone)
Speleothem (Calcium Carbonate, CaCO3)
Hag Stone
Naturally holed stone (typically sedimentary rock such as flint, limestone, or sandstone)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Gneiss (likely)
Gneiss
Anthracite Coal
Anthracite C
Ruby in Zoisite with Hornblende
Anyolite (Ruby: Al2O3, Zoisite: Ca2Al3(SiO4)3(OH))
Quartzite
Quartzite (primarily SiO2)
Blue Chalcedony
Chalcedony (Silicon Dioxide, SiO2)
Anthracite Coal
Anthracite
Greenstone
Protolith of basalt, diabase, or gabbro; often contains minerals like chlorite, actinolite, and epidote