Pearl
Organic gemstone (Calcium carbonate - CaCO3)
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.
Learn about Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material) in the encyclopedia
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Quartz (Milk Quartz / Massive Quartz)
Silicon Dioxide (SiO2)
mineral
Chert Nodule
Microcrystalline Silica (SiO2)
sedimentary
Quartz (Milky/Clear Quartz)
Silicon Dioxide (SiO2)
mineral
Quartz (Rose or Clear variety)
Silicon Dioxide (SiO2)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Fossilized Bone
Petrified Bone / Biogenic Sedimentary
fossil
Quartz (Cut and Polished Sphere)
Silicon Dioxide (SiO2)
mineral
Iron-stained quartz-rich rock, likely quartzite or silicified breccia
Quartz (SiO₂), possibly quartzite with limonite/goethite iron oxides
metamorphic
Polished mahogany obsidian
Volcanic glass (mostly SiO₂), commonly called mahogany obsidian
igneous
Fossilized Bone Fragment
Vertebrate Fossil
fossil
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Organic gemstone / Sedimentary mineraloid
Shark Tooth Fossil
Vertebrate fossilized tooth
fossil
Almandine Garnet
Iron aluminum silicate (Fe3Al2(SiO4)3)
mineral
Rhodonite
Rhodonite ((Mn2+,Fe2+,Mg,Ca)SiO3)
metamorphic
Tiger's Eye
SiO2 (Silicon Dioxide with Iron Oxide inclusions)
Mineral (Metamorphic pseudomorph)
Clear Quartz
Silicon dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Banded Agate (Onyx type)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
sedimentary
![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
Yellow Sapphire or Citrine
Al2O3 (Corundum) or SiO2 (Quartz)
mineral
White Quartz
Silicon Dioxide (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)
Pearl
Calcium Carbonate (Aragonite and Calcite), CaCO3
mineral
Quartz (Smoky/Clear variety)
Silicon Dioxide (SiO2)
mineral
Quartz (Variety: Rock Crystal Cluster)
Silicon Dioxide (SiO2)
mineral
Quartz Crystal Point
Silicon Dioxide (SiO2)
mineral
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
Mineral
Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite
mineral
Sandstone (with Moss)
Quartz Arenite / Sandstone
sedimentary
Amber
Fossilized Tree Resin (Amorphous Hydrocarbon)
Mineral
Quartz-bearing iron-stained breccia
Brecciated quartz/quartzite with iron oxides, chiefly SiO₂ with hematite/goethite and possible feldspar or host-rock fragments
mineral
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone (Whetstone/Sharpening Stone)
Siliciclastic Sandstone (SiO2 dominant)
sedimentary
Weathered mineralized rock fragment
Indeterminate; likely quartz–feldspar-rich lithic material with iron-oxide staining
mineral
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
mineral
Scoria (Volcanic Rock)
Scoria (often basaltic scoria)
Igneous
Green Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Agate (specifically Chalcedony nodule)
Silicon Dioxide (SiO2)
mineral