Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic (often found by beachcombers) specimens identified by the Rock Identifier community.
Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Graphite
Graphite (Carbon, C)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (primarily Silicon Dioxide, SiO2)
Chert (Jasper/Black Chert)
Silicon Dioxide (SiO2)
Chert (specifically Blue or Grey Chert/Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Chert (Septarian or Nodular variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Quartzite variety)
Microcrystalline Silica (SiO2)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Amber
Succinite (Resinite)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Amber
Resinite (Succinite if from the Baltic); Chemical Formula: C10H16O (approximate)
Jasper
Jasper (Silicon Dioxide, SiO2)
Chert Nodule (Fossiliferous Chert)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (variations include Flint/Jasper)
Chert (SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Banded Chert
Microcrystalline silicon dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (specifically Banded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (and its variety Flint)
Silicon Dioxide (SiO2) - Microcrystalline or cryptocrystalline Quartz
Chert (often called Flint or Jasper)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Chert (Yellow Chert/Flint)
Silicon Dioxide (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Chert (Arrowhead variety)
Chert (SiO2)
Chert (variant Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule / Geode fragment)
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Petrified Wood
Silicified wood (primarily SiO2 - Silicon Dioxide/Quartz)
Chert (with Quartz veins)
Microcrystalline quartz (SiO2)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Chert (specifically Flint)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide