Chert
Microcrystalline Quartz (SiO2)
Category
Browse marble specimens identified by the Rock Identifier community.
Chert
Microcrystalline Quartz (SiO2)
Quartzite Pebble
Quartzite (mostly SiO2)
Chalk / Sedimentary Limestone
Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock
Red Chert (Jasper)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite
Polished Chert (Flint)
Silicon Dioxide (SiO2)
Fossilized Shark Tooth
Elasmobranchii fossil (likely Odontaspididae family)
Honey Calcite
Calcium Carbonate (CaCO3)
Chalk (Calcitic)
Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock
Dolomite or Limestone (Carbonate Rock)
CaMg(CO3)2 (Dolomite) or CaCO3 (Limestone / Calcite)
Chert (Flint)
Microcrystalline or cryptocrystalline quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartz Pebble
Silicon Dioxide (SiO2)
Rough Diamond
Native Carbon (C)
Chert (Gravel Bit)
Microcrystalline silica (SiO2)
Brachiopod Fossil (Spiriferid)
Phylum Brachiopoda, Order Spiriferida (CaCO3 - Calcium Carbonate)
Limestone
Sedimentary Calcite (CaCO3)
Iron Meteorite (likely Chondrite or weathered Iron-Nickel)
Meteorite (Fe-Ni alloy & silicates)
Chert (containing Iron Oxide spots)
Microcrystalline Quartz (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Limestone (specifically Crushed Limestone/Calcictic)
Calcium Carbonate (CaCO3)
Basalt River Pebble
Basalt
Basalt
Basalt (Mafic volcanic rock)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Basalt Pebble
Extrusive mafic igneous rock
Quartz / Chert
Silicon Dioxide (SiO2)
Coquina
Biogenic Limestone (Calcite, CaCO3)
Chert (Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Nodule)
Chert (composed of Microcrystalline Silica/SiO2)
Diamond (in a jewelry setting)
Carbon (C)
Sandstone (likely Quartzose)
Clastic sedimentary rock (SiO2 primary)
Chert Pebble
Chert (Microcrystalline Quartz, SiO2)
Peridot
Olivine ((Mg, Fe)2SiO4)
Chert / Flint
Silicon Dioxide (SiO2)
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
Sandstone (Banded)
Clastic sedimentary rock (primarily SiO2)
Chert (Flint)
Chert (Cryptocrystalline Quartz, SiO2)
Chert Nodule (Flint)
Silicon Dioxide (SiO2)
Ferruginous Sandstone
Clastic Sedimentary Rock (Iron-rich)
Oolitic Chert
Oolitic Microcrystalline Quartz (SiO2)
Crinoid Stem Fossil
Class Crinoidea (Phylum Echinodermata), often preserved in Limestone or Calcite (CaCO3)
Siltstone
Siltstone (primarily composed of silica and clay minerals)