Serpentine (Nephrite-like River Cobble)
Serpentinite (Hydrous Magnesium Iron Silicate)
metamorphic
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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Tiger's Eye
Tiger's Eye (Pseudomorph of Quartz after Crocidolite), SiO2
Mineral
Blue Tiger's Eye (Hawk's Eye)
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Freshwater Pearl
Aragonite / Biogenic Calcium Carbonate (CaCO3)
mineral
Amygdaloidal Rhyolite
Rhyolite (felsic volcanic rock) with amygdules
igneous
Basalt with Epidote
Mafic volcanic rock with Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
igneous
Fossil Shark Tooth (embedded in matrix)
Lamniformes (likely Cretalamna or Squalicorax) within phosphatic/calcareous matrix
sedimentary
Connemara Marble
Ophiocalcite (Serpentinitic Marble)
metamorphic
Coquina (Fossiliferous Limestone)
Coquina (Organic Clastic Limestone)
sedimentary
Banded Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Basalt with Limonite stains
Extrusive mafic igneous rock; Limonite (FeO(OH)·nH2O)
igneous
Amber in Matrix
Succinite (Carbon-based organic polymer)
Organic (Sedimentary context)
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Amber
Succinite (fossilized resin)
Mineral
Amber
Succinite (fossilized tree resin)
Organic Mineraloid
Tree Agate (also known as Dendritic Agate)
Silicon Dioxide with inclusions (SiO2 + Mn/Fe)
mineral
Limonite with Quartz (Gossan)
Hydrated iron(III) oxide-hydroxide mixture (FeO(OH)·nH2O) with Silicon Dioxide (SiO2)
Mineral
Chrysocolla and Malachite Beads
Hydrated copper silicates (Chrysocolla) and Copper carbonate hydroxide (Malachite)
mineral
Chert (variant Flint)
Silicon Dioxide (SiO2)
sedimentary
Pallasite Meteorite (Sliced and Polished)
Pallasite (Iron-Nickel Matrix with Olivine crystals)
mineral
Chert (Cherty Limestone or Flint)
Microcrystalline Silica (SiO2)
sedimentary
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
mineral
Silicon
Silicon (Si)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of Iron Oxide)
metamorphic
Tiger's Eye
Silicon dioxide with fibrous inclusions (SiO2)
mineral
Unknown Organic Object (likely a berry or fruit)
Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.
Organic Material (likely a fruit or berry)
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Banded Gneiss (with Quartz Vein)
Gneiss (SiO2 and varied Silicates)
metamorphic
Chert (specifically Yellow/Brown Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Eudialyte
Eudialyte (Na4(Ca,Ce)2(Fe2+,Mn,Y)ZrSi8O22(OH,Cl)2)
mineral
Rhodonite
Rhodonite (Mn, Fe, Mg, Ca)SiO3
mineral
Tiger's Eye (Golden and Blue)
Silicon Dioxide (SiO2) with fibrous inclusions of Crocidolite
mineral
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Black Limestone with Calcite Veining
Bituminous Limestone (CaCO3 with Organic Carbon inclusions)
sedimentary
Red Tiger's Eye beads
Tiger's Eye (variety of Chalcedony, SiO2)
Mineral / Gemstone (variety of Quartz)
Bituminous Coal
Organic-rich sedimentary rock (Complex hydrocarbons)
sedimentary
Amber
(C10H16O)n – an amorphous organic substance, primarily composed of polymerized isoprenoids.
Mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
metamorphic
Megalodon Tooth
Otodus megalodon
sedimentary
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
metamorphic