Pearl
Calcium Carbonate (CaCO3) - Aragonite/Calcite organic gemstone
mineral
Category
Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)
Browse organic gemstone (not a rock or mineral in the traditional sense, but bio mineralized material) specimens identified by the Rock Identifier community.
Quartz (Milky/Clear Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz (Rose or Clear variety)
Silicon Dioxide (SiO2)
mineral
Clear Quartz
Silicon dioxide (SiO2)
mineral
Quartz (Milk Quartz / Massive Quartz)
Silicon Dioxide (SiO2)
mineral
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
mineral
Tiger's Eye
SiO2 (Silicon Dioxide with Iron Oxide inclusions)
Mineral (Metamorphic pseudomorph)
Amber
Fossilized Tree Resin (Amorphous Hydrocarbon)
Mineral
![Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral](https://media.rockidentification.com/59eef03b-830e-4d54-8641-241ee77e8bf0-thumbnail.jpg)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
mineral
Scoria (Volcanic Rock)
Scoria (often basaltic scoria)
Igneous
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
Mineral
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
mineral
Almandine Garnet
Iron aluminum silicate (Fe3Al2(SiO4)3)
mineral
Pearl
Calcium Carbonate (Aragonite and Calcite), CaCO3
mineral
Chert
Silicon dioxide (SiO2)
Sedimentary
Yellow Sapphire or Citrine
Al2O3 (Corundum) or SiO2 (Quartz)
mineral
Chalcedony
Cryptocrystalline Quartz (SiO2)
mineral
Baroque Pearl (and potentially a small Sapphire/Blue Topaz)
Pearl: Calcium Carbonate (aragonite or calcite) with conchiolin. Sapphire: Aluminum Oxide (Al2O3). Blue Topaz: Al2SiO4(F,OH)2.
Organic Gemstone (for pearl), Mineral (for sapphire/topaz)
Sandstone
Arenite
sedimentary
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Agate (specifically Chalcedony nodule)
Silicon Dioxide (SiO2)
mineral
Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite
mineral
Green Calcite
Calcite (CaCO3)
mineral
Anthracite Coal
Anthracite (a variety of coal, predominantly carbon)
Sedimentary Rock (Metamorphosed)
Massive Quartz
Silicon Dioxide (SiO2)
mineral
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
mineral
Yellow Jasper
Silicon Dioxide (SiO2) - variety of Chalcedony
sedimentary
![Turquoise (Hydrous phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral](https://media.rockidentification.com/bacc5567-052c-4219-b556-3474bdf7571f-thumbnail.jpg)
Turquoise
Hydrous phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
mineral
Amber / Copal
Succinite (fossilized tree resin)
mineraloid
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
sedimentary
Amber
Fossilized Tree Resin (C10H16O)
mineral
Chert (concretionary/nodular variant)
Microcrystalline Quartz (SiO2) with possible fossil or mineral inclusions
sedimentary
Limonite (Iron Ore)
Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)
Mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Sandstone
Arenicola (comprising mostly Quartz, SiO2)
sedimentary
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Amber
Succinite (Resinite), C10-H16-O
mineral
Garnet (likely Almandine or Pyrope)
Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)
Mineral
Pearl and Garnet Glass
Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass
mineral and glass