Sandstone
Arenicola (comprising mostly Quartz, SiO2)
Category
Browse organic (paper and cellulose) specimens identified by the Rock Identifier community.
Sandstone
Arenicola (comprising mostly Quartz, SiO2)
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (often called Flint or Jasper when pigmented)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (variations include Flint/Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Ironstone Concretion (Iron-rich Mudstone)
Siderite / Geothite concretion (FeCO3 / FeO(OH))
Pyrite (Fool's Gold) in Matrix
Iron Sulfide (FeS2)
Chert (specifically a nodule with Chalcendony/Agate banding)
Microcrystalline Quartz (SiO2)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (variations include Flint/Jasper)
Cryptocrystalline Silicon Dioxide (SiO2)
Chert (Iron-stained)
Chert (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
Fossilized Mammoth Tooth Fragment
Mammuthus primigenius (or Mammuthus sp.)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Travertine
Calcareous Tufa (CaCO3)
Chert (and Jasper/Flint variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Mother of Pearl (Nacre)
Aragonite (CaCO3) with Organic Matrix
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Chert (Arrowhead/Artifact Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Chert (specifically Red Chert / Flint)
Silicon Dioxide (SiO2)
Chert (Lightly weathered variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Limestone
Calcium Carbonate (CaCO3)
Limestone
Sedimentary rock composed mainly of calcium carbonate (CaCO3)
Fossiliferous Limestone
Sedimentary Calcium Carbonate (CaCO3) Matrix with Fossil Fragments
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Limestone (Fossiliferous)
Sedimentary Carbonate Rock (CaCO3)
Petrified Wood
Silicified wood (Quartz, SiO2)
Pyrite
Iron Disulfide (FeS2)
Ironstone Concretion
Siderite / Hematite-bearing Sedimentary Rock
Chert (Field Flint)
Microcrystalline Quartz (SiO2)
Shungite
Fullerene-bearing carbonaceous rock
Chert
Chert (Silica: SiO2)
Chert / Flint
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Green Chert
Microcrystalline Quartz (SiO2)
Chert (often called Flint for dark variants)
Microcrystalline or Cryptocrystalline Quartz (SiO2)