River Pebble (likely Quartzite or Chert)
Sedimentary Clast (Silicon Dioxide dominant)
sedimentary
Category
Not A Rock
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Orbicular Jasper (Ocean Jasper)
Silicon Dioxide (SiO2) with various inclusions
mineral
Sandstone Cobble
Clastic Sedimentary (Sandstone)
sedimentary
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Chert / Chalcedony (likely carnelian or flint variety)
Silicon Dioxide (SiO2)
sedimentary
Mixed rock collection
Labeled specimens appear to include iron-rich rock, schist, basalt, serpentinite, and shale
igneous, sedimentary, metamorphic
Sandstone (Ferruginous)
Arenite (Siliclastic Sedimentary Rock)
sedimentary
Horn Coral Fossil
Rugosa (Tetracoralla)
fossil
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
sedimentary
Quartz Vein in Matrix (Breccia / Host Rock with Quartz)
Silicon Dioxide (SiO2) in Host Rock Matrix
metamorphic
Rounded granite cobble
Granite; predominantly quartz, alkali feldspar, plagioclase, and mica
igneous
Pegmatitic gneiss with a quartz–feldspar vein
Quartz–feldspar-rich gneiss, locally cut by a granitic pegmatite vein
metamorphic
Weathered granite or granitic gneiss
Felsic granitoid; primarily quartz, feldspar, and mica
igneous
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
mineral
Basalt
Aphanitic Mafic Igneous Rock
igneous
Sandstone or possibly a conglomerate
Arenite (if sandstone)
sedimentary
Granite
Felsic intrusive igneous rock
igneous
Tumbled serpentine or serpentinite
Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; approximate formula Mg₃Si₂O₅(OH)₄
metamorphic
Quartz Geode
Silicon Dioxide (SiO2) within a sedimentary or igneous host
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Basalt with Amygdales
Amygdaloidal Basalt
igneous
Tumbled green stone, likely serpentine
Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, chrysotile)
metamorphic
Serpentine (polished/tumbled)
Serpentine-group minerals, chiefly antigorite, Mg₃Si₂O₅(OH)₄
metamorphic
Rounded basalt pebble
Fine-grained mafic volcanic rock, commonly basalt (plagioclase + pyroxene ± olivine)
igneous
Basalt
Mafic extrusive igneous rock
igneous
Basalt with Quartz Veining
Veined Basalt (composed primarily of plagioclase feldspar, pyroxene, and olivine with quartz/calcite infill)
igneous
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
igneous
Quartzite River Pebble
Quartzite (primarily Silicon Dioxide, SiO2)
metamorphic
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Porphyritic Basalt (Drill Core)
Porphyritic Basalt with Plagioclase Phenocrysts
igneous
Ferruginous Sandstone (Ironstone)
Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))
sedimentary
Schist
Mica Schist (contains muscovite/biotite and quartz)
metamorphic
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Sedimentary Rock (possibly a conglomerate or coarse-grained sandstone)
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Basalt with Quartz Veins
Basalt with Quartz or Calcite Veining
igneous
Quartz with inclusions (likely Chlorite or Hornblende) and country rock
SiO2 (Quartz) with associated ferromagnesian minerals
Mineral/Igneous/Metamorphic association
Granite Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
sedimentary
River cobble (Greywacke/Sandstone)
Sandstone / Greywacke
sedimentary
Fine-grained, banded rock (possibly gneiss)
Unidentified foliated silicate rock; composition cannot be determined from this close-up
metamorphic
Glacial Cobble (likely Granitic or Gneissic)
Granite/Gneiss Glacial Erratic
igneous
Quartzite (probable)
Quartzite; predominantly recrystallized quartz (SiO₂)
metamorphic