Limestone
Calcium Carbonate (CaCO3)
Category
Browse sedimentary like (industrial composite) specimens identified by the Rock Identifier community.
Limestone
Calcium Carbonate (CaCO3)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Chert (with potential fossil inclusion)
Microcrystalline Quartz (SiO2)
Sandstone (Glacial Cobble)
Arenite / Sedimentary Rock (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
Chert / Microcrystalline Quartz
Silicon Dioxide (SiO2)
Flint / Chert
Silicon dioxide (SiO2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Chert
Microcrystalline Quartz (SiO2)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Sand Dollar Fossil (Echinoidea)
Class Echinoidea (likely order Clypeasteroida), CaCO3 (Calcite)
Conglomerate
Conglomerate (clastic sedimentary rock)
Chert (v. Flint)
Chert (Microcrystalline Quartz, SiO2)
Banded Chert
Silicon Dioxide (SiO2)
Galena
Lead(II) sulfide (PbS)
Chert (Common Opal or Flint variant)
Microcrystalline Quartz (SiO2)
Chert (Quartz)
Silicon Dioxide (SiO2)
Limonite (Ironstone)
Goethite/Limonite (Hydrated iron(III) oxide-hydroxide)
Garnet in Matrix
Almandine Garnet (Fe3Al2(SiO4)3)
Sandstone Concretion
Ferruginous Sandstone Concretion
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Jasper (specifically Bloodstone/Heliotrope or Dark Green Jasper)
Cryptocrystalline Quartz (SiO2) with inclusions
Sulfur (with possible Cullet Glass or Slag imitation)
Native Sulfur (S8)
Rhodonite
Manganese Inosilicate (Mn,Fe,Mg,Ca)SiO3
Chert (and Flint)
Silicon Dioxide (SiO2)
Chert (with Limestone matrix)
Chert (Silica: SiO2)
Red Dyed Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Optical Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Gneiss (Banded Gneiss)
Gneiss
Quartz Mica Schist
Mica-Quartz Schist (Chemical: SiO2 + KAl2(AlSi3O10)(OH)2)
Chalcedony Geode Fragment
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Cryptocrystalline quartz (SiO2)
Chert (White Chert/Flint)
Chert (Cryptocrystalline Silica or Microcrystalline Quartz, SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (SiO2 based typically)
Sandstone (lithic/greywacke variety)
Arenite (composed primarily of SiO2 with various lithic fragments)
Quartz
Silicon Dioxide (SiO2)
Specular Hematite with Pyrite
Iron Oxide (Fe2O3) with Iron Sulfide (FeS2)