Pegmatite
Coarse-grained Igneous Rock (Granitic Pegmatite)
Category
Browse mineral, possibly rock fragment containing a mineral specimens identified by the Rock Identifier community.
Pegmatite
Coarse-grained Igneous Rock (Granitic Pegmatite)
Milky Quartz with Mineral Inclusions
Quartz (Silicon Dioxide, SiO2)
Fossilized Bone Fragment
Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)
Sandstone (with cross-bedding)
Arenite (composed primarily of Quartz: SiO2)
Chalcedony Nodule (Agate/Chert)
Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)
Amygdaloidal Basalt
Vesicular-Amygdaloidal Basalt (Mafic Extrusive)
Amygdaloidal Basalt
Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)
Siltstone/Sandstone (possibly Wonderstone or Picture Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide inclusions)
Granodiorite
Granodiorite
Green Aventurine
Silicon Dioxide (SiO2) with inclusions
Pegmatite (Granite Pegmatite)
Intrusive Igneous Rock (Granite Pegmatite)
Conglomerate
Conglomerate (Clastic sedimentary rock)
Fossiliferous Limestone (Coquina / Shell Limestone)
Bioclastic Limestone (CaCO3)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Biotite (Black Mica)
Biotite - K(Mg,Fe)3(AlSi3O10)(OH)2
Shale
Shale (Sedimentary rock composed of mud/clay minerals)
Amygdaloidal Basalt
Amygdaloidal Basalt
Banded Rock (likely Quartz-rich)
Uncertain, likely a Metamorphic Rock (e.g., Gneiss or Schist) with prominent Quartz and other minerals
Note: No specimen visible
Granitic Pegmatite
Pegmatitic Granite
Quartz Pebble
Silicon Dioxide (SiO2)
Vesicular Basalt with Amygdules
Amygdaloidal Basalt
Moss Agate
Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)
Schist
Mica Schist (Medium-grade Metamorphic Rock)
Greisen (Quartz-Muscovite-Turretine Rock)
Greisen
Granite (Weathered)
Phaneritic Felsic Igneous Rock
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic silicate with secondary mineral inclusions)
Granite
Granite (High-silica plutonic rock)
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Amygdaloidal Basalt
Amygdaloidal Basalt containing Zeolite or Quartz (SiO2/Silicates)
Shale
Fissile Mudstone (Shale)
N/A - Non-Geological Item
Mica-rich Schist fragment
Mica Schist
Quartz (Gravel fragment)
Quartz (Silicon Dioxide, SiO2)
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Basalt
Basalt (primarily composed of Plagioclase Feldspar and Pyroxene)
Shale
Lutaceous sedimentary rock
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock)
Shale
Fissile mudstone (primarily clay minerals and silt-sized quartz)
Geode (Unopened)
Siliceous Geode (SiO2)
Herkimer Diamond
Quartz (Silica - SiO2)