Rock Identifier

Category

Mineral Variant

Browse mineral variant specimens identified by the Rock Identifier community.

Nickel coin (U.S. currency) (Cupronickel (75% Copper, 25% Nickel alloy)) — man-made alloy (metallic)

Nickel coin (U.S. currency)

Cupronickel (75% Copper, 25% Nickel alloy)

man-made alloy (metallic)

Boxwork Siderite or Sepatarian Nodule Weathering (Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment) — sedimentary

Boxwork Siderite or Sepatarian Nodule Weathering

Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Fluorite with Quartz coating (Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)) — mineral

Fluorite with Quartz coating

Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic Volcanic Rock)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)

Peacock Ore (Bornite (Cu5FeS4) or iridescent Chalcopyrite (CuFeS2)) — mineral

Peacock Ore

Bornite (Cu5FeS4) or iridescent Chalcopyrite (CuFeS2)

Green Fluorite (Fluorite (Calcium Fluoride, CaF2)) — mineral

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Granite (Phaneritic plutonic rock (Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Phaneritic plutonic rock (Quartz, Alkali Feldspar, and Plagioclase)

Green Fluorite (likely synthetic or heat-treated for jewelry) (Calcium Fluoride (CaF2)) — mineral

Green Fluorite (likely synthetic or heat-treated for jewelry)

Calcium Fluoride (CaF2)

Sandstone (Arenite (SiO2 based with various mineral cements)) — sedimentary

Sandstone

Arenite (SiO2 based with various mineral cements)

Limonite (Oxidized Iron Ore) (FeO(OH)·nH2O (Hydrous ferric oxide)) — mineral

Limonite (Oxidized Iron Ore)

FeO(OH)·nH2O (Hydrous ferric oxide)

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Limonite (Yellow Ochre) (Hydrated iron(III) oxide-hydroxides (FeO(OH)·nH2O)) — mineral

Limonite (Yellow Ochre)

Hydrated iron(III) oxide-hydroxides (FeO(OH)·nH2O)

Limonite (Iron Ore) (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Limonite/Goethite Nodule (Iron Oxyhydroxide (primarily FeO(OH)·nH2O)) — mineral

Limonite/Goethite Nodule

Iron Oxyhydroxide (primarily FeO(OH)·nH2O)

Granite (Granite (Felsic Intrusive Igneous Rock)) — igneous

Granite

Granite (Felsic Intrusive Igneous Rock)

Bauxite (Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)) — sedimentary

Bauxite

Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)

Sandstone (Ferruginous) (Arenite (Fe2O3 staining)) — sedimentary

Sandstone (Ferruginous)

Arenite (Fe2O3 staining)

Diorite (River Rock/Cobble) (Intermediate Plutonic Igneous Rock (Diorite)) — igneous

Diorite (River Rock/Cobble)

Intermediate Plutonic Igneous Rock (Diorite)

Gneiss (Gneiss (High-grade regional metamorphic rock)) — Metamorphic

Gneiss

Gneiss (High-grade regional metamorphic rock)

Diorite (Phaneritic intermediate plutonic rock) — igneous

Diorite

Phaneritic intermediate plutonic rock

Note regarding baguette production (not a rock) (Digital text image - Somali language) — not a rock

Note regarding baguette production (not a rock)

Digital text image - Somali language

Epidote in Matrix (Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)) — metamorphic

Epidote in Matrix

Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

Arsenopyrite in Quartz Matrix (Arsenopyrite (FeAsS) with Quartz (SiO2)) — mineral

Arsenopyrite in Quartz Matrix

Arsenopyrite (FeAsS) with Quartz (SiO2)

Black Sand (Magnetite Sand) (Magnetite (Fe3O4)) — mineral

Black Sand (Magnetite Sand)

Magnetite (Fe3O4)

Sandstone (Arenite (SiO2 + various cementing minerals)) — sedimentary

Sandstone

Arenite (SiO2 + various cementing minerals)

Amygdaloidal Basalt (Amygdaloidal Basalt (with secondary mineral infilling)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (with secondary mineral infilling)

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Gneiss (Gneiss (High-grade metamorphic rock)) — metamorphic

Gneiss

Gneiss (High-grade metamorphic rock)

Granite Pebble (Weathered) (Phaneritic Felsic Igneous Rock) — igneous

Granite Pebble (Weathered)

Phaneritic Felsic Igneous Rock

Banded Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (Metamorphic Rock)

Black Spinel (Magnesium Aluminum Oxide (MgAl2O4)) — mineral

Black Spinel

Magnesium Aluminum Oxide (MgAl2O4)

Cobaltian Calcite (Cobalt-bearing Calcite (Ca,Co)CO3) — mineral

Cobaltian Calcite

Cobalt-bearing Calcite (Ca,Co)CO3

Amygdaloidal Basalt (Amygdaloidal Mafic Volcanic Rock) — igneous

Amygdaloidal Basalt

Amygdaloidal Mafic Volcanic Rock

Magnetite Sand (Black Sand) (Magnetite (Fe3O4)) — mineral

Magnetite Sand (Black Sand)

Magnetite (Fe3O4)

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Malachite and Azurite on Gossan (Ironstone Matrix) (Cu2CO3(OH)2 (Malachite) on FeO(OH)·nH2O (Limonite/Gossan)) — mineral

Malachite and Azurite on Gossan (Ironstone Matrix)

Cu2CO3(OH)2 (Malachite) on FeO(OH)·nH2O (Limonite/Gossan)

Fluorite (Calcium fluoride (CaF2)) — mineral

Fluorite

Calcium fluoride (CaF2)

Blue Apatite (Fluorapatite (Ca5(PO4)3F)) — mineral

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Vesuvianite (Idocrase) (Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10) — mineral

Vesuvianite (Idocrase)

Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10

Bornite (Bornite (Cu5FeS4)) — mineral

Bornite

Bornite (Cu5FeS4)