Chert (often called Flint)
Silicon Dioxide (SiO2)
Category
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Chert (often called Flint)
Silicon Dioxide (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Ironstone Concretion / Limonite Node
Goethite and Limonite (FeO(OH) nH2O)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Jasper
Silicon dioxide (SiO2)
Chert (with Limestone and Iron Oxide staining)
Cryptocrystalline Quartz (SiO2)
Chert (specifically Yellow/Tan Chert)
Silicon Dioxide (SiO2)
Jasper
Jasper (Cryptocrystalline variety of Quartz, SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Amber
Succinite (Resinous fossilized tree sap)
Chert (Tan/Brown)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Black Dolomite
Bituminous Dolomite (CaMg(CO3)2)
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide / SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Glauconitic Sandstone
Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert
Cryptocrystalline Quartz (SiO2)
Chert (Chert / Flint)
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Pyritic Mudstone
Argillaceous rock (FeS2)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Petrified Wood
Silicified Wood (SiO2)
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Chert Nodule (with Chalcedony)
Chert (SiO2) / Cryptocrystalline Quartz
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Green Calcite
Calcium Carbonate (CaCO3)
Amber
Succinite (organic fossilized resin)
Chert (Nodular Chert)
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Ferruginous Sandstone (Ironstone)
Sedimentary rock with Limonite/Goethite cement
Chert (Chert Nodule with Cortex)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (potentially Jasper/Common Opal mixture)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Ironstone variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Chalcedony)
Silicon Dioxide (SiO2)