Tufa (Limestone)
Calcareous Tufa (CaCO3)
sedimentary
Category
Mineral (Silicate Replaced Organic Material)
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Learn about Mineral (Silicate Replaced Organic Material) in the encyclopedia
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Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Organic Gemstone (Biogenic)
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)
mineral
Sandstone
Arenite (SiO2 primarily)
sedimentary
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
sedimentary
Dendritic Agate / Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Precious Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
mineral
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions
mineral
Tiger's Eye and Carnelian Quartz
Silicon Dioxide (SiO2)
metamorphic and mineral
Blue Tiger's Eye
Crocidolite (fibrous riebeckite) silicified to Quartz (SiO2)
Mineral
Sandstone
Arenite (SiO2 based)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Schist
Mica Schist
metamorphic
Chert Pebble with Inclusion
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone
Arenite (Clastic Sedimentary Rock)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Yellow Chert (Chert / Cryptocrystalline Quartz)
Silicon Dioxide (SiO2)
sedimentary
Sandstone Cobble
Arenite (Secondary classification based on grain size)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Fossilized Coral (Favosites)
Favosites (extinct genus of tabulate coral)
sedimentary
Petoskey Stone
Hexagonaria percarinata
fossil
Chert (Flint variety)
Microcrystalline context of Quartz (SiO2)
sedimentary
Chert Pebble
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Pearl
Calcium carbonate (CaCO3) + organic conchiolin (Biogenic Mineral)
mineral
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Jasper and Aquamarine (likely)
Jasper (Cryptocrystalline Quartz (SiO2)), Aquamarine (Beryl (Be3Al2Si6O18))
Sedimentary (Jasper), Mineral (Aquamarine)
Prase quartz with actinolite inclusions
Silicon dioxide (SiO2) with Calcium Magnesium Iron Silicate Hydroxide inclusions
mineral
Sandstone (Quartzose Sandstone)
Arenite
sedimentary
Sandstone (Quartzose)
Arenite (SiO2 based)
sedimentary
Sandstone (Ferruginous)
Sandstone (primarily SiO2 with iron oxide cement Fe2O3)
sedimentary
Quartz Chip
Silicon Dioxide (SiO2)
mineral
Chrysocolla in Matrix
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Silicate/Secondary Copper Mineral)
mineral
Moss Agate
Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)
mineral
Amber
Fossilized Tree Resin (C10H16O)
mineral
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Limonite pseudomorph after Pyrite
Goethite/Limonite FeO(OH)·nH2O
mineral
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz (specifically Milky/Gray Quartz vein)
Silicon Dioxide (SiO2)
mineral
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary