Anthracite Coal
Anthracite
Category
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Anthracite Coal
Anthracite
Placer Gold Nugget
Native Gold (Au)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Conglomerate
Conglomerate (lithified rudite)
Greenschist
Greenschist (Chlorite Schist)
Mica Schist
Mica Schist (primarily Muscovite or Biotite-rich sequence)
Milky Quartz
Silicon Dioxide (SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Green Aventurine
Silicon dioxide (SiO2) with inclusions of Fuchsite
Epidote
{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
Gneiss (specifically a Banded Gneiss pebble)
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Pyrite (Limonite Pseudo-morph after Pyrite)
Iron sulfide (FeS2) transitioning to Iron oxide-hydroxide (FeO(OH)·nH2O)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Pyrite
Iron Disulfide (FeS2)
Grey Slate
Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)
Gneiss (specifically a granitic gneiss cobble)
Gneiss (high-grade regional metamorphic rock)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Diamond
Natural Carbon (C)
Marble
Recrystallized Calcite (CaCO3)
Quartz (Common Milky Quartz)
Silicon Dioxide (SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Quartz (likely tumbled or naturally water-worn)
Quartz (SiO₂ - Silicon Dioxide)
Blue Calcite
Calcium Carbonate (CaCO3)
Chert (Arrowhead/Projectile Point)
Microcrystalline Quartz (SiO2)
Gneiss
Gneiss
Banded Gneiss
Gneiss (Metamorphic rock composed of feldspar, quartz, and mica)
Gneiss
Gneiss
Gneiss (specifically a Banded Gneiss cobble)
Gneiss (composed mainly of Quartz, Feldspar, and Biotite/Amphibole)
Ruby (Raw/Rough)
Corundum (Al2O3 with Chromium trace)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz / Rock Crystal
Silicon Dioxide (SiO2)
Greenschist
Chlorite schist
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Gneiss
Gneiss
Gneiss (Metamorphic Cobble)
Gneiss
Gneiss (Schistose)
Gneiss
Gneiss
Gneiss