Chalk
Calcium Carbonate (CaCO3)
Category
Browse limestone specimens identified by the Rock Identifier community.
Chalk
Calcium Carbonate (CaCO3)
White Marble
Recrystallized Calcite / Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2)
Chert (Brown Chert / Flint)
Silicon Dioxide (SiO2)
Chert (Flint Arrowhead)
Microcrystalline Quartz (SiO2)
Pyrite
Iron Disulfide (FeS2)
Fluorite Geode
Calcium Fluoride (CaF2)
Chert (Red Jasper variant)
Silica (SiO2)
Chert (or Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Jasperoid)
Silicon Dioxide (SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Favosites Fossil (Honeycomb Coral)
Favosites (Extinct genus of tabulate coral)
Chert (Yellow Jasper variant)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert
Microcrystalline Silicon Dioxide (SiO2)
Chert (specifically Brown Chert or Flint)
Cryptocrystalline Quartz (SiO2)
Quartz Geode (Cracked)
Silicon Dioxide (SiO2)
Chert (Iron-stained)
Chert (Microcrystalline and Cryptocrystalline Quartz, SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Chert (and/or Chalcedony)
Microcrystalline Silica (SiO2)
Banded Chert (or Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Arrowhead variety)
Chert (SiO2)
Chert (and/or Flint)
Microcrystalline Quartz (SiO2)
Fossil Coral
Scleractinia (fossilized calcium carbonate)
Chert (often called Flint when dark or found in chalk)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically a Worked Flint/Knapped Flake)
Chert / Flint (Microcrystalline Quartz, SiO2)
Banded Chert or Agate
Silicon Dioxide (SiO2)
Dyed Quartz Geode
Dyed crystalline quartz (Silicon Dioxide, SiO2)
Chert (Jasper/Flint variant)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Chert (SiO2)
Calcite (Optical Calcite / Iceland Spar)
Calcium Carbonate (CaCO3)
Yellow Quartzite (River Cobble)
Quartzite (mainly SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline silica (SiO2)
Quartz Druzy (Geode Fragment)
Silicon Dioxide (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Pink Chert or Jasperized Chert)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Quartz)
Silicon Dioxide (SiO2)
Chert / Jasper
Microcrystalline Quartz (SiO2)
Chert / Jasper and River Stones
Microcrystalline Quartz (SiO2)