Quartzite
Quartzite (SiO2)
Category
Browse limestone specimens identified by the Rock Identifier community.
Quartzite
Quartzite (SiO2)
Fossilized Coral (Petoskey Stone type)
Hexagonaria percarinata (Fossilized Rugose Coral)
Chert (Light Variety)
Sedimentary cryptocrystalline quartz (SiO2)
Travertine
Terrestrial Sedimentary Rock (CaCO3)
Quartzite River Pebble
Quartzite (primarily SiO2)
Chert / Flint Conglomerate
Silicified Sedimentary Breccia (primarily SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Chalk
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Orange Calcite (Carved as a Horned Skull)
Calcium Carbonate (CaCO3)
Chert / Flint
Cryptocrystalline quartz (SiO2)
Chert (specifically a stream-worn Chert Nodule)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert Nodule (Flint)
Microcrystalline quartz (SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Fossil Coral (Favosites Honeycomb)
Favosites (Genus), Phylum Cnidaria, Class Anthozoa
Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)
SiO₂ (silicon dioxide)
Chert (within Limestone)
Silicon Dioxide (SiO2)
Chert (potentially Fossiliferous or Jasperoid)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Geode (Unopened)
SiO2 (Silicon Dioxide) - Chalcedony/Quartz Geode
Chert (variations include Flint/Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Travertine (Tufa)
Travertine (Aragonite/Calcite form of Calcium Carbonate, CaCO3)
Chert (Agatized Chert)
Microcrystalline Quartz (SiO2)
Chert (Tan/Yellow variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Geode (Unopened)
Silica Concretion / Geode (Formula: SiO2 for quartz internal contents)
Chert (White-Tan variety)
Silicon dioxide (SiO2) / Microcrystalline Quartz
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Belemnite Fossil
Belemnitida (Order of extinct cephalopods)
Marcasite Concretion (Propeller/Sand Dollar shape)
Marcasite (FeS2)
Fossilized Brachiopod
Phylum Brachiopoda (General mineral composition: Calcite/CaCO₃ or Silica/SiO₂)
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Chert (Tan/Brown variety)
Chert (Silicon Dioxide, SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Drupa Quartz (Sparkly Drusy Quartz on Matrix)
Crystalline Silicon Dioxide (SiO2) on host rock
Chert / Flint Nodules
Cryptocrystalline Quartz (SiO2)
Fossilized Brachiopod Shell
Phylum Brachiopoda (likely Order Spiriferida or Strophomenida)
Quartzite
Quartzite (SiO2)
Chert (specifically Flint or Common Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Commonly known as Flint)
Microcrystalline Quartz (SiO2)
Chert (Commonly known as Flint or Jasper when pigmented)
Microcrystalline or Cryptocrystalline Quartz (SiO2)