Chert (Common Opal variant)
Microcrystalline Quartz (SiO2)
Category
Browse limestone specimens identified by the Rock Identifier community.
Chert (Common Opal variant)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Cryptocrystalline quartz (SiO2)
Chert (Iron-stained)
Chert / Microcrystalline Silicon Dioxide (SiO2)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Fossil Shark Tooth
Carcharodon sp. (likely Otodus or similar Lamniformes order)
Calcite Geode
Calcium Carbonate (CaCO3)
Yellow Calcite
Calcium Carbonate (CaCO3)
Optical Calcite (Iceland Spar)
Calcite (CaCO3)
Geode (unopened) or Calcareous Nodule
Siliceous or Calcareous Concretion/Nodule
Calcite
Calcium Carbonate (CaCO3)
Flint / Chert
Silicon dioxide (SiO2)
Lapis Lazuli
Lapis Lazuli (Complex silicate: Na8[Al6Si6O24]Sn)
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
Marble
Recrystallized Calcite (CaCO3)
Celestite (Celestine) Geode
Strontium Sulfate (SrSO4)
Flint (Chert)
Silicon Dioxide (SiO2)
Chert (Black Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (and Limestone)
Chert (consisting of Microcrystalline Quartz, SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Coquina Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Septarian Nodule (Dragon Stone)
Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)
Orthoceras Fossil Limestone
Orthoceras sp. (Calcium Carbonate, CaCO3)
Chert
Microcrystalline silica (SiO2)
Crinoid Columnal Fossil
Class Crinoidea (Echinodermata); usually calcite replacement (CaCO3)
Crinoid Fossil in Limestone
Class Crinoidea in Carbonate Matrix (CaCO3)
Fossilized Pycnodonte Oyster
Pycnodonte (Gryphaeostrea) species; Composition is Calcium Carbonate (Calcite/Aragonite)
Limestone (Ocherous)
Calcium Carbonate (CaCO3) with Iron Oxide (Limonite)
Oolitic Limestone
Oolite (Sedimentary rock composed of CaCO3)
Fossiliferous Limestone
Calcite-rich Sedimentary Rock (CaCO3)
Crushed Limestone
Sedimentary Calcium Carbonate (CaCO3)
Dendritic Limestone
Calcite with Manganese Oxide (Manganese Dendrites)
Limestone (Weathered)
Calcium Carbonate (CaCO3)
Limestone Breccia
Sedimentary Breccia (Calcareous)
Limestone with Calcite Veins
Sedimentary Calcium Carbonate (CaCO3)