Unidentified Rock Fragment
Unknown
Rock
Category
Sedimentary Or Metamorphic (Base Substrate)
Browse sedimentary or metamorphic (base substrate) specimens identified by the Rock Identifier community.
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Kyanite (within Quartz)
Kyanite (Al2SiO5) in crystalline Quartz base (SiO2)
metamorphic
Biotite Schist
Biotite Schist (K(Mg,Fe)3AlSi3O10(OH,F)2)
metamorphic
Coarse Sand or Fine Gravel
Detrital Sedimentary Fragments (mostly SiO2)
sedimentary
Basalt Pebble
Extrusive Igneous Rock
igneous
Gneiss (Pebble)
Gneiss
metamorphic
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
mineral
Muscovite Schist
Muscovite Schist (KAl2(AlSi3O10)(OH)2 matrix)
metamorphic
Banded Gneiss
Banded Gneiss (High-grade Metamorphic Rock)
metamorphic
Quartzite with Chert inclusions
Metamorphosed Quartz-rich Rock (SiO2)
metamorphic
Quartz
Silicon Dioxide (SiO2)
mineral
Gneiss
High-grade Metamorphic Gneiss
metamorphic
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Mica Schist
Mica Schist (primarily Muscovite or Biotite-rich sequence)
metamorphic
Muscovite
KAl2(AlSi3O10)(OH)2
mineral
Mica Schist with Quartz
Mica Schist (principally Muscovite and Biotite with Quartz veins)
metamorphic
Mica Schist
Mica Schist (Composition: Muscovite, Biotite, Quartz, Feldspar)
metamorphic
Gneiss (High-grade Metamorphic Rock)
Gneiss
metamorphic
Muscovite Schist with Quartz
Mica Schist (KAl2(AlSi3O10)(OH)2 with SiO2)
metamorphic
Muscovite Mica Schist
Metamorphic Rock (Muscovite-Biotite Schist)
metamorphic
Epidote
Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)
mineral
Quartz Mica Schist
Mica-Quartz Schist (Chemical: SiO2 + KAl2(AlSi3O10)(OH)2)
metamorphic
Quartz / Quartzite
Silicon Dioxide (SiO2)
metamorphic
Dragon Blood Jasper
Epidote and Pietersite-rich Quartz (SiO2 with inclusions)
sedimentary
Mica Schist with Quartz
Mica-Quartz Schist (Muscovite subclass)
metamorphic
Gneiss (Hornblende/Biotite Gneiss)
Foliated Metamorphic Rock (Quartz-Feldspar-Amphibole/Mica matrix)
metamorphic
Map Jasper (Picasso Stone)
Metamorphosed Calcium Carbonate (Crystalline Limestone or Marble with Silicate inclusions/impurities)
metamorphic
Green Kyanite
Kyanite (Al2SiO5)
mineral
Mixed pebble collection, including likely flint, quartzite, and fossil material
Varied silicate rocks; visible specimen may include chert (microcrystalline SiO₂), quartzite, and a possible fossil
sedimentary
Kyanite (in Schist Matrix)
Kyanite (Al2SiO5)
metamorphic
River Stones (Quartzite and Sandstone)
Quartzite / Sedimentary Rock (SiO2 dominant)
sedimentary
Mica Schist
Mica Schist (primarily Muscovite and Biotite)
metamorphic
Mica Schist with Garnet
Almandine-Mica Schist
metamorphic
Quartzite
Quartzite; predominantly microcrystalline quartz (SiO₂)
metamorphic
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Mica Schist
Muscovite Schist (KAl2(AlSi3O10)(OH)2)
metamorphic
Graphite
Graphite (Native Carbon, C)
Mineral
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Feldspathic Gneiss
High-grade Metamorphic Rock (Gneiss)
metamorphic
Emerald / Green Beryl
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
mineral