Pearl
Aragonite (CaCO3 with conchiolin)
Category
Browse not a rock (man made polymer) specimens identified by the Rock Identifier community.
Pearl
Aragonite (CaCO3 with conchiolin)
Red Chert (Jasper)
Cryptocrystalline Quartz (SiO2) with iron oxide inclusions
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Flint (or Chert)
Cryptocrystalline Quartz (SiO2)
Quartzite (River Pebble)
Quartzite (Mainly SiO2)
Chert (Iron-stained)
Chert (Microcrystalline and Cryptocrystalline Quartz, SiO2)
White Jade (Nephrite)
Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2
Fordite
Anthropogenic paint-rock
Chert (Jasper Variant likely)
Silicon Dioxide (SiO2)
Bismuth Crystal
Bismuth (Bi)
Fossilized oyster shell
Bivalvia; likely an oyster (Ostreidae), partly mineralized with calcite
Jasper Marble
Silicon Dioxide (SiO2) with Impurities
Pebble
Clast (specifically a granule or small pebble)
Amethyst (or Light Amethyst / Rose Quartz)
Quartz (Silicon Dioxide, SiO2)
Coquina / Fossiliferous Limestone
Fossiliferous Limestone (Calcite, CaCO3)
Chert Nodule
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Chert (Flint)
Chert (SiO2)
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Chert (Common Variety, Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Sunstone
Andesine-Labradorite Feldspar ((Ca,Na)(Al,Si)4O8)
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Chert (Nodule)
Chert (Alpha-Quartz, SiO2)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert / Flint
Silicon Dioxide (SiO₂)
Tumbled milky quartz
Quartz (silicon dioxide, SiO₂)
Banded Calcite or Travertine
Calcium Carbonate (CaCO3)
Diamond
Carbon (C)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Quartzite
Silica (SiO2) quartzite
Chert (often called Flint or Jasper)
Microcrystalline Quartz (SiO2)
Crinoid Stem Segment Fossil
Crinoidea (columnal ossicle)
Fossilized Shark Tooth (Sand Tiger)
Carcharias sp. (Fossilized Tooth)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities