Sandstone
Arenite
sedimentary
Category
Organic Gemstone (Not A Rock Or Mineral)
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Not A Rock Or Mineral) in the encyclopedia
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Moss Agate
Silicon Dioxide (Chalcedony with green mineral inclusions), SiO2
gemstone
Moss Agate
Chalcedony (Silicon Dioxide - SiO2) with inclusions
Mineral
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Organic gemstone / Sedimentary mineraloid
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron
mineral
Chert with Calcite Veins
Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions
sedimentary
Sandstone with Quartz Crystal Infill
Quartz-cemented quartz arenite
sedimentary
Fossilized Bivalve Shell
Class Bivalvia (fossilized)
fossil
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide
mineral
Amber
Fossilized Tree Resin (Succinate)
mineral
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
mineral
Quartz Vein Rock
Silicon dioxide (SiO2) within a host rock matrix
mineral
Concretion
Septarian or Siderite Concretion
sedimentary
Black Freshwater Pearls
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Red Sandstone
Sandstone (Quartz Arenite / Arkose with Hematite cement)
sedimentary
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
mineral
Possible fossilized shell or coral fragment
Indeterminate biogenic carbonate, likely calcite (CaCO₃)
fossil
Amber
Fossilized Tree Resin (Organic Polymer)
gemstone
Amber
Succinite (approximate formula C10H16O)
mineral
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
sedimentary (matrix) / mineral (inclusion)
Agate (Moss or Dendritic Agate)
Chalcedony (Silicon Dioxide, SiO2)
mineral
Amber
Succinicum (Organic polymer, largely C10H16O)
Organic Mineral
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
mineral
Emerald (or possibly Green Glass / Slag)
Beryl (Be3Al2(SiO3)6)
gemstone
Pearl
Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified wood (SiO2)
fossil
Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
mineral
Amber (Raw Copal)
Fossilized Plant Resin (Gummite/Succinite)
mineral
Chert (Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily Quartz/SiO2)
mineral
Amber
Succinite (approximate formula C10H16O)
mineral
Black Pearl (Tahitian-style Cultured Pearl)
Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)
mineral
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Chert with Quartz Vein
Silicon dioxide (SiO2)
sedimentary
Fossiliferous Limestone (Coquina)
Calcite (CaCO3) with Bioclastic inclusions
sedimentary
Amber
Succinite (C10H16O)
mineraloid
Amber
Succinite (amorphous organic polymer)
mineral
Geode (Unopened)
SiO2 (Quartz-filled Sedimentary Nodule)
sedimentary
White seed-bead gemstone strand, likely freshwater pearl or shell pearl
Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image
gemstone