Pink Opal
Hydrated Silica (SiO2·nH2O)
Category
Browse organic (mineraloid) specimens identified by the Rock Identifier community.
Pink Opal
Hydrated Silica (SiO2·nH2O)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mg/Mn/Chlorite)
Petrified Wood
Silicified Wood (primarily SiO2)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
Amber
Succinite (fossilized tree resin)
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Shale (with minor calcite veining)
Clastic sedimentary rock (primarily clay minerals and quartz)
Moss Agate
Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
Fancy Jasper
Jasper (Cryptocrystalline Quartz, SiO2)
Chert (Jasper)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Jasper type)
Microcrystalline Quartz (SiO2)
Yellow Chert (River Stone)
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth
Bioapatite (Calcium Hydroxyapatite) replacement
Flint
Chert (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Jasper
Jasper (Cryptocrystalline variety of Quartz, SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Jasper
Silicon Dioxide (SiO2) with impurities
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert / Jasper
Cryptocrystalline Silica (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Chert (SiO2)
Chert (or Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Basanite / Jasper)
Microcrystalline quartz (SiO2)
Chert (Chert Nodule)
Silicon Dioxide (SiO2)
Chert Pebble with Inclusion
Microcrystalline Quartz (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert (Jasper/Common Chert Pebble)
Microcrystalline Quartz (SiO2)
Bivalve Fossil in Sedimentary Matrix
Fossiliferous Mudstone (Class: Bivalvia)
Chert (Flint)
Microcrystalline Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (often called Flint when found in chalk)
Microcrystalline Quartz (SiO2)
Chert / Flint
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Green Jasper
Jasper (Silicates, SiO2)
Chert (Gravel)
Silicon Dioxide (SiO2)
Chert (Jasper/Common Opal mix)
Microcrystalline Quartz (SiO2)
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
Chert (Jasper-bearing)
Microcrystalline silica (SiO2) with iron oxide inclusions