Chert (specifically Flint or Jasper variant)
Cryptocrystalline Quartz (SiO2)
Category
Browse organic mineraloid specimens identified by the Rock Identifier community.
Chert (specifically Flint or Jasper variant)
Cryptocrystalline Quartz (SiO2)
Orthoceras Fossil Limestone
Orthoceras sp. (Calcium Carbonate, CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Chert (Quartz Variety)
Chert (Silicon Dioxide, SiO2)
Chert / Jasper / Agate (Chalcedony Group)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (principally SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (often called Flint or River Rock)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert / Flint
Chert (SiO2)
Banded Chert
Silicon Dioxide (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (White Chert)
Silicon Dioxide (SiO2)
Chert (River Siltstone/Flint)
Chert (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Red Chert (Jasper)
Chert / Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint Pebble)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Fossil Shark Tooth (Otodus obliquus)
Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))
Carbonaceous Chondrite (CV3 type)
Carbonaceous Chondrite (CV3 group)
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Amber
Succinite (C10H16O)
Fossil Coral (Rugosa or Solitary Coral)
Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)
Chert (Holey Stone)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Sandy Ironstone
Ferruginous Sandstone
Fossiliferous Chert
Silicon Dioxide (SiO2) with fossil inclusions
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
Shale
Mudrock / Fissile Shale
Baltic Amber (Black)
Succinite (Fossilized Tree Resin)
Amber
Resinite (Succinite if from the Baltic); Chemical Formula: C10H16O (approximate)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides
Shale
Shale (clay-sized silicate minerals)
Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Limestone with Calcite Veining
Sedimentary Carbonate Rock (CaCO3)
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
Petrified Wood
Silicified Wood (SiO2)
River Rock
Silica-rich water-worn rock
Limestone (Weathered)
Calcium Carbonate (CaCO3)
White seed-bead gemstone strand, likely freshwater pearl or shell pearl
Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image