Chert (containing Iron Oxide)
Microcrystalline Quartz (SiO2)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Chert (containing Iron Oxide)
Microcrystalline Quartz (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Mookaite Jasper
Silicified Radiolarite (SiO2 with iron impurities)
Pyrite
Pyrite (Iron Disulfide), FeS2
Chert (often called Flint)
Silicon Dioxide (SiO2)
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (C10H16O)
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)
Chert (Jasper/River Stone)
Silicon dioxide (SiO2) - Microcrystalline quartz
Ironstone Concretion (Limonite/Goethite)
Iron oxide concretion (contains FeO(OH)·nH2O)
Petrified Wood
Silicified Wood (SiO2)
River Pebble (Siltstone/Mudstone)
Clastic sedimentary rock
Chert (variations include Flint or Jasper)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
Fossiliferous Limestone (Coquina / Shell Limestone)
Bioclastic Limestone (CaCO3)
Yellow Chert
Sedimentary cryptocrystalline quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2 permineralization)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Chert (specifically Gray/Black Chert)
Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Zebra Rock / Zebra Marble
Banded Limestone-Marble Transition
Amber
Succinite (organic mineraloid); Chemical formula: C10H16O
Chert / Greenstone
Silicon Dioxide (SiO2) with impurities
Glauconitic Sandstone
Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (and Flint)
Chert (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Glauconitic Sandstone
Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Glauconitic Sandstone
Glauconitic Sandstone (contains (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Chert (Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Basanite variety)
Microcrystalline Quartz (SiO2)
Chert (Chert / Flint)
Silicon Dioxide (SiO2)
Chert (White Flint)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone with Brachiopod shell
Calcium carbonate (CaCO3)
Green Jasper
Silicon Dioxide (SiO2)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Fossil Coral (Rugose Coral Fragment)
Rugosa (extinct order of solitary and colonial corals)
Chalk
Calcium Carbonate (CaCO3)