Yellow Ochre / Limonite
Limonite (FeO(OH)·nH2O)
Mineral
Category
Organic (Non Rock)
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Red Quartzite
Quartzite (primarily SiO2)
metamorphic
Quartzite River Rock
Metamorphic Rock (Recrystallized Quartz - SiO2)
metamorphic
Quartzite
Quartzite (SiO2-rich metamorphic rock)
metamorphic
Quartzite
Quartzite (primarily SiO2)
metamorphic
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Common Opal in Host Rock
Hydrated Silica (SiO2·nH2O)
mineraloid
Precious Opal in Matrix
Hydrated Silica (SiO2·nH2O)
mineral
Quartzite
Metamorphic Rock (Mainly SiO2)
metamorphic
Granite
Granite (Plutonic Igneous Rock)
igneous
Granite
Granite (Felsic Plutonic Rock)
igneous
Seashell Fossil
Gastropoda fossil
fossil
Quartzite
Quartzite (SiO2-rich metamorphic rock)
metamorphic
Anthracite Coal
Anthracite (Carbon-based metamorphic rock)
metamorphic
Quartz Geode / Druzy Quartz
Silicon Dioxide (SiO2)
mineral
Geode (Unopened)
SiO2 (Quartz-filled Sedimentary Nodule)
sedimentary
Starfish Fossil
Asteroidea fossil
fossil
Glauconitic Sandstone
Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Quartz-rich granitic rock, possibly pegmatite
Granite/pegmatitic granite; chiefly quartz (SiO₂), feldspar, and mica
igneous
Fossiliferous Limestone with Rugose Coral
Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)
sedimentary
Fossilized coral (likely honeycomb or branching coral)
Fossil coral; probable Scleractinia or Tabulata, composition mainly microcrystalline CaCO₃
fossil
Quartzite River Rock
Quartzite (primarily SiO2)
metamorphic
Quartzite River Rock
Metaquartzite (majorly SiO2)
metamorphic
Coal
Bituminous Coal / Anthracite
sedimentary
Raw Emerald in Matrix
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Anthracite Coal
Anthracite (Carbon-based sedimentary-metamorphic rock)
metamorphic
Tumbled green aventurine (probable)
Quartzite dominated by quartz (SiO₂), with green fuchsite mica inclusions
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Obsidian (Black Obsidian)
Amorphous volcanic glass (primarily SiO2)
igneous
Greenstone (Celadonite-bearing Volcanic)
Hydrothermally altered basalt or andesite with Celadonite (K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2)
metamorphic
Basalt River Pebble
Mafic Igneous Rock (Fine-grained Basalt)
igneous
Limestone
Calcareous sedimentary rock (CaCO3)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Limestone Pebble
Sedimentary Rock (Calcite, CaCO3)
sedimentary
Sandstone
Sandstone (Quartz-rich Arenite / SiO2)
sedimentary
Black-and-white granite
Granite, primarily quartz–feldspar–biotite aggregate
igneous
Polished agate/geode fragment
Microcrystalline quartz (chalcedony), SiO₂, with possible calcite or quartz cavity lining
mineral
Quartzite
Metamorphosed Quartz Sandstone
metamorphic
River Cobble (Sandstone)
Arenite (primarily SiO2)
sedimentary
Chert (Jasper type)
Microcrystalline Quartz (SiO2)
sedimentary
Quartzite
Quartzite (Metamorphic rock composed primarily of quartz)
metamorphic
Obsidian with Slate/Tuff
Volcanic glass (SiO2) with associated pyroclastic rock
igneous