Glauconitic Sandstone
Glauconitic Sandstone (Greensand)
Category
Browse marble specimens identified by the Rock Identifier community.
Glauconitic Sandstone
Glauconitic Sandstone (Greensand)
Banded Chert
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline silica (SiO2)
Diamond (or high-quality simulant like Cubic Zirconia)
Carbon (C) - Native Element
Pearl
Calcium Carbonate (Aragonite and Calcite), CaCO3
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Diamond
Carbon (C)
Chalk
Micrite (primarily Calcium Carbonate, CaCO3)
Pearl (incorporated into jewelry)
Aragonite and Calcite (CaCO3)
Chert (and Jasper/Chalcedony mixture)
Microcrystalline Quartz (SiO2)
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Peridot (Olivine)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Amber Chert (Jasper)
Microcrystalline Quartz (SiO2)
Pearl
Organic Mineral (CaCO3 with conchiolin)
Fossiliferous Limestone with Brachiopod
Phylum Brachiopoda in calcitic matrix
Chert (varieties: Flint or Chalcedony)
Microcrystalline silica (SiO2)
Mixed Gemstone Collection
SiO2 (Quartz varieties) and Biogenic CaCO3 (Nacre)
Serpentinite
Serpentine rock (Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4
Sandstone (with potentially high Feldspar/Arkose content)
Clastic sedimentary rock (SiO2 dominated)
Orange Calcite
Calcium Carbonate (CaCO3)
Serpentinite
Serpentinite (group of hydrous magnesium iron phyllosilicates)
Fossilized Sea Urchin (Echinoid)
Echinoidea (Fossil specimen, often replaced by Calcite or Silica)
Fossil Bivalve Shell
Class Bivalvia (e.g., Veneriidae family)
Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite
Fighting Conch (Sea Shell)
Strombus alatus (primarily composed of Calcium Carbonate / CaCO3)
Caribbean Calcite
Calcium Carbonate (CaCO3) with Aragonite (CaCO3)
Limestone
CaCO3 (principally Calcite)
Shungite
Non-crystalline carbonoid (Shungite)
Chert (Flint) Nodule
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartz (Chert/Chalcedony variety)
Silicon Dioxide (SiO2)
Pearl (likely Freshwater or Akoya Cultured)
Aragonite / Conchiolin composite (CaCO3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (SiO2)
Mookaite Jasper
Radiolarite (SiO2 with impurities)
Chert (Yellow Jasper/River Pebble)
Microcrystalline Quartz (SiO2)
Serpentine
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Coquina or Fossilized Shell Aggregate
Calcareous bioclastic sedimentary rock (CaCO3)
Fossilized Echinoid (Sea Urchin)
Echinoidea (Class), often found as calcitic fossils
Glauconite
(K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2