Yellow Agate
Silicon Dioxide (SiO2)
mineral
Category
Metamorphic Or Sedimentary Depending On Local Grade
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Pink Feldspar
Orthoclase Feldspar (KAlSi3O8)
mineral
Epidote in Matrix (Unakite-related)
Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))
metamorphic
Anthracite Coal
Low-grade metamorphic carbonaceous rock
metamorphic
Slate with Iron Staining
Low-grade Metamorphic Mudstone (Slate)
metamorphic
Eclogite
Eclogite (Omphacite + Pyrope)
metamorphic
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
metamorphic
Basalt with Epidote (Greenstone)
Epidote-bearing Metabasalt
metamorphic
Nuummite
Nuummite (ortho-amphibole rock)
metamorphic
Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)
There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).
Mineral
Granite Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
metamorphic
Epidote (likely Unakite component or Epidosite)
Epidote (Ca2(Al2Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Rutilated Quartz
Quartz (SiO2) with Rutile (TiO2) inclusions
Mineral
Epidote in Quartz
Quartz with Epidote inclusions (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH) inclusions)
Mineral
Schist
Mica Schist (primarily composed of quartz, feldspar, and mica)
metamorphic
Mica Schist
Muscovite/Biotite Schist
metamorphic
Black Sapphire
Corundum (Al2O3 with iron and titanium impurities)
mineral
Rough Quartz in Pegmatite Matrix
Quartz (Silicon Dioxide - SiO2) in Granitic Pegmatite
igneous
Limonite-stained Quartz / Quartzite
Silicon Dioxide (SiO2) with iron hydroxides (FeO(OH)·nH2O)
sedimentary or metamorphic
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Banded Gneiss
Gneiss
Metamorphic
Quartzite with Gneissic Banding
Quartzite (primarily SiO2) with mafic mineral inclusions
metamorphic
Alexandrite
Chrysoberyl (BeAl2O4 with Chromium impurities)
mineral
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
mineral
Rhodonite
Manganese Inosilicate (MnSiO3), often with Ca, Fe, Mg, Zn
Mineral
Staurolite (Cross Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
metamorphic
Sodalite
Sodalite, Na8(Al6Si6O24)Cl2
Mineral
Rhodonite
Rhodonite (MnSiO3)
Mineral
Diamond
Diamond (pure carbon C)
mineral
Schorl (Black Tourmaline)
Sodium Iron Aluminum Borosilicate Hydroxide - NaFe2+3Al6Si6O18(BO3)3(OH)3OH
mineral
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
metamorphic
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
metamorphic
Eclogite
Eclogite (Pyrope garnet and Omphacite pyroxene)
metamorphic
Diamond
Native Carbon (C)
mineral
Conglomerate
Conglomerate
Sedimentary
Schist
Mica Schist (Quartz-Muscovite-Biotite Schist)
metamorphic
Epidote in Matrix
Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Nuummite
Nuummite (intergrowth of orthoamphiboles Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)
metamorphic
Gneiss
Gneiss (a type of metamorphic rock)
Metamorphic Rock
Calcite
Calcite (CaCO₃, Calcium Carbonate)
Mineral
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Mineral