Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Category
Browse organic (geological interest) specimens identified by the Rock Identifier community.
Pyrite in Shale
Iron Sulfide (FeS2) in Argillaceous Shale
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂)
Pyrite
Pyrite (FeS2)
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
Quartz Geode
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Geode (Unopened)
Silica-rich concretion (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Graphite Schist
C (Carbonaceous Schist)
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Black Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Mixed Quartz and Jasper Pebbles
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (principally Silicon Dioxide, SiO2)
Brick
Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)
Chert (Brown variety / Common Jasper)
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper locally)
Chert (Microcrystalline Quartz, Formula: SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
River Stone (Chert/Siltstone)
Cryptocrystalline Quartz (SiO2) with trace impurities
Puddingstone
Conglomerate (specifically a type of jasper conglomerate or quartz conglomerate)
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcedony replacement)
Petrified Wood
Silicified Wood (SiO2)
Chert Nodule
Microcrystalline Silica (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Caliche (also known as hardpan, calcrete, kankar)
Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.
Moss Agate
Silicon Dioxide with inclusions (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Cherty Flint/Jasper variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Graphite
Graphite (Native Carbon, C)
Chert (Nodule)
Silicon Dioxide (SiO2)
Fossiliferous Shale Matrix
Clastic Sedimentary Rock with Brachiopod or Mollusk shell fragments
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (and Petrified Wood)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities