Limestone
Calcium Carbonate (CaCO3)
Category
Browse organic gem material (botanical) specimens identified by the Rock Identifier community.
Limestone
Calcium Carbonate (CaCO3)
Concrete with Aggregate
Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)
Sandstone (with manganese staining)
Clastic sedimentary rock (primarily SiO2)
Sandstone (with potential Arkose/Lithic characteristics)
Arenite (Sedimentary rock composed of sand-sized grains)
Fossiliferous Limestone
Limestone (CaCO3 - Calcium Carbonate)
Pyrite in Shale
Iron Disulfide (FeS2) in Argillaceous Shale
Green Moss Agate
Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite
Pink Opal
Amorphous Hydrous Silica (SiO2·nH2O)
Amber
Succinicum (Succinite); C10H16O
Pink Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Amber
Succinite (specifically for Baltic amber; fossilized tree resin)
Moss Agate and Hematite
Silica (SiO2) with fibrous inclusions of Manganese or Iron; Hematite (Fe2O3)
Chert (Common Opal variant)
Microcrystalline Quartz (SiO2)
Amber
Amber (C10H16O)
Asphalt Concrete (Bituminous Pavement)
Aggregates in Bitumen Matrix
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Greenschist
Greenschist facies rock (containing chlorite, actinolite, and epidote)
Yellow Ochre / Limonite
Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)
Slag (Industrial Byproduct)
Artificial silicate/iron byproduct
Limonite (Iron Ore Congcretion)
Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)
Fossiliferous Limestone
CaCO3 (principally Calcite or Aragonite)
Chert (Beach Pebble)
Silicon Dioxide (SiO2)
Chert (specifically Red Chert/Jasper variety)
Silicon Dioxide (SiO2)
River Stone (Chert/Siltstone)
Cryptocrystalline Quartz (SiO2) with trace impurities
Chert (with Quartz Veining)
Microcrystalline silicon dioxide (SiO2)
Chert (often referred to as Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (Iron-stained)
Chert / Microcrystalline Silicon Dioxide (SiO2)
Glauconitic Sandstone
Glauconitic Quartz Arenite
Chert
Chert (SiO2)
Chert (Yellow Jasper/Flint)
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Chert (Tan/Grey)
Chert (Silicon Dioxide, SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Common Chert)
Chert (Cryptocrystalline Silica, SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
Chert (White Chert or Flint)
Microcrystalline or cryptocrystalline quartz (SiO2)
Chert (Fossiliferous)
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (Quartz Variety)
Chert (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)