Dumortierite Quartz (Blue Quartz)
Al7BO3(SiO4)3O3 with Quartz (SiO2)
mineral
Category
Metamorphic (Modified)
Browse metamorphic (modified) specimens identified by the Rock Identifier community.
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Pyrite (or Arsenopyrite / Ore mineral aggregate)
FeS2 (Iron Sulfide)
mineral
Pyrite or Chalcopyrite
Iron sulfide (FeS2) or Copper iron sulfide (CuFeS2)
mineral
Chalcopyrite
CuFeS2 (Copper Iron Sulfide)
mineral
Agate
SiO2
Mineral/Gemstone
Orthoclase Feldspar
Potassium aluminum silicate (KAlSi3O8)
mineral
Feldspar (Plagioclase / Potassium Feldspar)
Feldspar Group (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8)
mineral
Greenstone
Metabasalt / Greenschist
metamorphic
Epidotite (Unakite-related Epidote)
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Schist (likely Mica Schist)
Mica Schist
metamorphic
Gneiss
Metamorphic Gneiss (High-grade regional metamorphism)
metamorphic
Gneiss
Metamorphic rock of high-grade regional metamorphism
metamorphic
Gneiss
Metamorphic Gneiss (High-grade regional metamorphism)
metamorphic
Milky quartz-rich rock
Quartz, silicon dioxide (SiO₂), likely massive milky quartz with iron-oxide or feldspar impurities
mineral
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2AlSi3O10(OH)2
mineral
Quartzite pebble
Quartzite (SiO2 based)
metamorphic
Quartz in Matrix (Lepidolite or Quartzite)
Silicon Dioxide (SiO2) with host rock
mineral
Greenish Feldspathic Rock / Epidote Granite (Unakite-type or Epidote-bearing rock)
Epidotized Metamorphic/Igneous Rock
metamorphic
Garnet fragments
Garnet-group silicate, most likely almandine–pyrope or spessartine; composition varies, commonly (Fe,Mg,Mn)₃Al₂Si₃O₁₂
mineral
Green aventurine (likely)
Quartz variety, SiO₂, colored commonly by fuchsite mica or chlorite
mineral
Biotite mica
Biotite, a potassium-rich mica in the annite–phlogopite series; approximate formula K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂
mineral
Biotite mica (likely)
Biotite, a mica-group mineral; approximate formula K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂
mineral
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Pink Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)
mineral
Ruby (faceted gemstone)
Corundum (Al2O3 with Cr impurities)
gemstone
Blue Kyanite
Kyanite (Al2SiO5)
mineral
Black Tourmaline (Schorl)
NaFe3+3Al6(BO3)3Si6O18(OH)4
mineral
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Labradorite
(Na, Ca)(Si, Al)4O8
mineral
Nephrite Jade
Ca2(Mg, Fe)5Si8O22(OH)2
metamorphic
Milky Quartz with Nephrite Jade
Silicon Dioxide (SiO2) with Ca2(Mg,Fe)5Si8O22(OH)2
mineral/metamorphic
Rounded gray river cobble
Likely fine-grained sandstone, siltstone, or metamorphosed equivalent; exact identification requires a fresh surface and tests
sedimentary
Banded gneiss pebble
Gneiss, typically quartz–feldspar–mica assemblage
metamorphic
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Igneous
Jasper in Rhyolite matrix
Silicon Dioxide (SiO2) with various inclusions in Felsic Igneous matrix
igneous
Greenstone / Greenschist
Chlorite schist / Epidiorite
metamorphic
Slate
Foliated Metamorphic Rock (composed mainly of clay minerals or micas)
metamorphic
Rhodonite
Rhodonite, manganese inosilicate — MnSiO₃; the specimen may include quartz, feldspar, and black manganese-oxide minerals in the matrix
mineral
Epidote
Epidote (Ca2(Al,Fe)3(SiO4)3(OH))
mineral
Schist or Gneiss pebble
Metamorphic rock (Schist/Gneiss)
metamorphic
Gneiss
High-grade Metamorphic Gneiss
metamorphic
Slate
Foliated metamorphic rock (Slate)
metamorphic