Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Category
Browse man made object (coin) specimens identified by the Rock Identifier community.
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Chert (Common Variety, Jasper)
Microcrystalline Quartz (SiO2)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Chert (Alpha-Quartz, SiO2)
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Chert / Flint
Silicon Dioxide (SiO₂)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Ironstone (Limonitic Sandstone)
Ferruginous Sandstone (rich in Limonite: FeO(OH)·nH2O)
Crazy Lace Agate
Silicon dioxide (SiO2) - a variety of banded Chalcedony (cryptocrystalline quartz)
Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Calcite
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Yellow Calcite
Calcium Carbonate (CaCO3)
Nephrite Jade
Nephrite (a variety of the Calcium magnesium iron silicate mineral series Actinolite), Ca2(Mg, Fe)5Si8O22(OH)2
Tiger's Eye
Silicon dioxide (SiO2) with fibrous inclusions of crocidolite
Chert (Common Opal/Jasper variety)
Cryptocrystalline Quartz (SiO2)
Chert (and/or Flint)
Microcrystalline Quartz (SiO2)
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
Diamond (in jewelry setting)
Carbon (C)
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
Smoky Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite
Chert (often called Flint)
Chert (SiO2)
Diamond (in jewelry setting)
Adamantine Carbon (C)
Basalt
Basalt (Mafic volcanic rock)
Diorite
Intermediate plutonic igneous rock
Sea Shell (Fighting Conch Fragment)
Calcium Carbonate (CaCO3) - Strombus alatus fragment
Granite
Granite (Felsic Plutonic Rock)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
White Marble
Recrystallized Calcite (CaCO3)
Chrysocolla in Malachite
Cu2CO3(OH)2 (Malachite) / Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla)
Aragonite (specifically Mexican Marbled Onyx)
Aragonite (Calcium Carbonate, CaCO3)
Obsidian (Black)
Obsidian (High-silica volcanic glass)
Chert (or Flint)
Chert (cryptocrystalline quartz), SiO2
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock
Granite Pebble
Felsic intrusive igneous rock
Calcite
Calcium Carbonate (CaCO3)
Jasper
Silicon Dioxide (SiO2)