Ferruginous Sandstone (Ironstone)
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Category
Browse organic (anthropogenic) specimens identified by the Rock Identifier community.
Ferruginous Sandstone (Ironstone)
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Petrified Wood
Silicified Wood (SiO2)
Fossiliferous Brachiopod in Shale
Brachiopoda (Phylum) preserved in Carbonaceous Shale
Jasper with Quartz Vein
Silicon Dioxide (SiO2) with impurities
Petrified Wood (Silicified Wood)
Silicified Wood / Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Chert (specifically Jasper or Flint variant)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Mudstone)
Silicon Dioxide (SiO2)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Field Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (White Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Tan/Buff Chert)
Microcrystalline Quartz (SiO2)
Chert (often colloquially referred to as Flint)
Chert (Cryptocrystalline Quartz, SiO2)
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (Green variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (Microcrystalline Quartz), SiO2
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
Chert (Jasper/Iron-stained Quartzite)
Silicon Dioxide (SiO2)
Chert Pebble (with Quartz Vein)
Chert (Cryptocrystalline Silica - SiO2)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Chert (vuggy variety)
Microcrystalline silica (SiO2)
Chert (Flint)
Chert (Cryptocrystalline Quartz, SiO2)
Chert (Nodule)
Chert (primarily Microcrystalline Quartz - SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert (specifically Yellow Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Smooth River Pebble)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (specifically River Stone / Jasper variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)