Anthracite Coal
Carbon (with trace impurities)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Anthracite Coal
Carbon (with trace impurities)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Glauconitic Sandstone (Greensand)
Glauconitic Sandstone (Iron-potassium phyllosilicate mineral: (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Chert / Jasper
Silicon Dioxide (SiO2)
Chert (Green variety)
Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert (Black Chert / Flint)
Silicon Dioxide (SiO2)
Emerald in Matrix
Beryl (Be3Al2Si6O18) with Quartz/Schist
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Amber
Succinite (Fossilized Tree Resin)
Petrified Wood with Lichen
Silicified Wood (SiO2) colonized by crustose lichens
Moss Agate
Chalcedony (SiO2 with inclusions)
Chert (variously known as Flint)
Microcrystalline quartz (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (Jasper variation)
Chert (Cryptocrystalline microcrystalline Silicon Dioxide, SiO2)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Chert (with potential fossil inclusion)
Microcrystalline Quartz (SiO2)
Quartz Geode
Silicon Dioxide (SiO2) within a geode
Amber
Succinite (Fossilized Resin)
Glauconite (Greensand)
Glauconite (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Amber Dragonfly Brooch
Succinited (Baltic Amber)
Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified Wood (SiO2)
Knightia Fossil in Limestone
Knightia eocaena in micritic limestone
Amber
Succinite (amorphous organic polymer)
Amber
Succinates (Organic Fossilized Resin)
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
Amber
Succinite (Fossilized Tree Resin)
Zebra Jasper
Opaque microcrystalline Quartz (SiO2) with impurities
Amber
Succinite (fossilized resin)
Fossiliferous Limestone
Calcium carbonate matrix with macrofossils (CaCO3)
Amber
Succinate (Organic Fossilized Resin)
Amber
Succinite (Resin C10H16O)
Amber
Succinite (a fossilized organic resin)
Chert Arrowhead
Chert (Cryptocrystalline variety of Quartz, SiO2)
Brown Pebble (Probable Chert or Siltstone)
Silicon Dioxide (SiO2) / Sedimentary Microcrystalline Quartz
Granite
Intrusive Igneous Rock
Amber-bearing Coal/Sedimentary Rock
Bituminous coal or carbonaceous siltstone with Fossilized Tree Resin (C10H16O)
Petrified Wood
Silicified Wood (SiO2)