Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Category
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (and/or River Pebble)
Microcrystalline quartz (SiO2)
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3) - Bioclastic Limestone
Purple Agate (Dyed Chalcedony)
SiO2 (Silicon Dioxide) with organic dyes
Chert (Pink Jasper)
Microcrystalline Quartz (SiO2)
Chert (and Flint)
Silicon dioxide (SiO2) - Microcrystalline quartz
Amber
Succinite (fossilized resin, C10H16O)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Tan or Buffer variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Chert Nodule
Microcrystalline Silica (SiO2)
Chert (often called Flint)
Chert (SiO2)
Fossilized Coral
Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)
Chert / Flint
Microcrystalline or cryptocrystalline quartz (SiO2)
Jasper
Silicon dioxide (SiO2)
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
Amber
Succinite
Chert (specifically Yellow/Tan Chert)
Silicon Dioxide (SiO2)
Ironstone Concretion / Limonite Node
Goethite and Limonite (FeO(OH) nH2O)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Chert Pebble
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Amber
Succinite (fossilized resin)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert (Chalcedony)
Silicon Dioxide (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Chert / Flint)
Silicon Dioxide (SiO2)
Chert (Tan/Brown)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Jasper/Ironstone variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Amber
Succinite (Resinous fossilized tree sap)
Glauconitic Sandstone
Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Chert (Jasper-bearing)
Microcrystalline silica (SiO2) with iron oxide inclusions
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Chert (with Limestone and Iron Oxide staining)
Cryptocrystalline Quartz (SiO2)
Chert (Chert Nodule with Cortex)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (Nodular Chert)
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide / SiO2)