Sandstone
Arenite (primarily SiO2)
Category
Browse sedimentary (biogenic) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily SiO2)
Chert (Flint)
Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)
Chert (Flint Nodules)
Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Limonite (Ironstone)
Limonite (FeO(OH)·nH2O)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Common Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Milky Quartz with Iron Inclusions
Quartz (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Conglomerate
Conglomerate (SiO2 primary clasts with lithic matrix)
Basalt River Stone
Basalt
Milky Quartz in Matrix
Silicon Dioxide (SiO2)
Chert (and Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (often called Flint in dark varieties)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Sandstone
Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)
Chert (Iron-stained)
Chert (Cryptocrystalline Silica, SiO2)
Yellow Quartzite (Onyx Pebble)
Silicon Dioxide (SiO2) - Quartzite
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Megalodon Shark Tooth Fossil
Otodus megalodon
Quartz (Druzy)
Silicon Dioxide (SiO2)
Banded Siltstone or Argillite
Siltstone (primarily SiO2 with Al and Fe oxides)
Quartz River Cobble
Silicon Dioxide (SiO2)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Sandstone with Manganese Dendrites/Oxide coatings
Arenite with Pyrolusite and Romanechite (MnO2)
Yellow Quartzite (River Stone)
Quartzite (primarily SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (varieties include Flint and Mudstone)
Microcrystalline Silica (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Conglomerate
Conglomerate (SiO2, Al2O3, Fe2O3, CaCo3)
Chert / Flint
Chert (Cryptocrystalline Silica, SiO2)
Riverstone Jasper (Chert variant)
Silicon Dioxide (SiO2)
Piddock bored rock (Boring Stone)
Ichnofossil-bearing Limestone or Mudstone (trace fossils by Pholadidae)
Chert (Jasper)
Microcrystalline Quartz (SiO2) with iron oxide impurities
Brain Coral Fossil
Family Mussidae or Merulinidae (Order Scleractinia)
Concretion
Septarian concretion (likely containing Calcite or Siderite)
Fossil Shark Tooth (Cretaceous white shark type)
Squalicorax (commonly known as Crow Shark)