Fossilized Rugose Coral (Horn Coral)
Order Rugosa
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Fossilized Rugose Coral (Horn Coral)
Order Rugosa
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
Glauconite (Greensand Articulated Sandstone)
Glauconite ((K, Na)(Fe, Al, Mg)2(Si, Al)4O10(OH)2)
Chert (Smooth River Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Amber / Copal
Succinite (fossilized tree resin)
Petrified Wood
Silicified wood (primarily SiO2)
Red Moss Agate (Jasper)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Green Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe)
Chert (often called Jasper or River Siltstone)
Microcrystalline Quartz (SiO2)
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
Chert (Nodule)
Microcrystalline quartz (SiO2)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of cellulose)
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Chert (Light Variety)
Sedimentary cryptocrystalline quartz (SiO2)
Crushed Limestone
Sedimentary Calcium Carbonate (CaCO3)
Chert (White Chert or Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
Fossil Coral (Rugose Coral Fragment)
Rugosa (extinct order of solitary and colonial corals)
Black Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Jasper)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (and Limestone Pebbles)
Silicon Dioxide (SiO2) / Sedimentary Microcrystalline Quartz
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
Jasper
Silicon dioxide (Microcrystalline Quartz, SiO2)
Chert (Gravel pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossilized Shark Tooth
Bioapatite (Calcium Hydroxyapatite) replacement
Chert (Jasper/Common Opal mix)
Microcrystalline Quartz (SiO2)
Chert / Flint
Chert (Cryptocrystalline Silica, SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Jasper or Agate (Chalcedony)
Silicon Dioxide (SiO2) with impurities
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline silica (SiO2)
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Calcareous biomicrite / Calcium Carbonate (CaCO3)