Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
Red Jasper
Microcrystalline Quartz (SiO2) with Hematite impurities
Sandstone
Arenite (SiO2, often with CaCO3 or Fe2O3 cement)
Sandstone
Sandstone (clastic sedimentary rock)
Greywacke (likely)
Greywacke (a type of sandstone)
Amber
Succinite (a fossilized organic resin)
Black Pearl (Tahitian Type)
Aragonite / Pinctada margaritifera (CaCO3 + Conchiolin)
Rough Amber (likely Copal or immature Amber)
Organic gemstone / Succinite (if Baltic)
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Amber
Amber (Amorphous Organic Hydrocarbon)
Chert (and Fossilized Brachiopod shell)
Sedimentary Cryptocrystalline Quartz (SiO2)
Amber / Copal
Succinite (fossilized tree resin)
Moss Agate
Silicon Dioxide with inclusions (SiO2)
Chert (Arrowhead Preform)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Pearl (likely Freshwater or Akoya Cultured)
Aragonite / Conchiolin composite (CaCO3)
Gray Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Amber
Succinite (fossilized tree resin)
Black Pearl (Tahitian-style Cultured Pearl)
Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)
Amber
Organic gemstone (Succinite is common if from the Baltic)
Chert Arrowhead (Projectile Point)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Moqui Marbles
Iron Oxide Concretion (Hematite/Goethite)
Chert (often called Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (specifically Flint)
Microcrystalline Quartz (SiO2)
Chert (Tan/Brown)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert / Flint
Chert (SiO2)
Chert (Yellow or Brown Jasper)
Microcrystalline Quartz (SiO2)
Chert (Flint variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Glauconitic Sandstone (Greensand)
Glauconitic quartz wacke or arenite
Chert (often called Flint or Jasper when red)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Pink Jasper)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Chert (Iron-stained variant)
Microcrystalline Quartz (SiO2)
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2) / Microcrystalline Quartz
Anthracite Coal
Anthracite