Biotite Schist
Biotite-rich Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)
metamorphic
Category
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Cobaltian Calcite (Cobaltoan Calcite)
Cobalt-bearing Calcite (Ca,Co)CO3
mineral
Goniatite Fossil
Goniatitida (Order), fossilized in limestone/calcite (CaCO3)
sedimentary
Fulgurite
Fulgurite (Lechatelierite), amorphous SiO2
metamorphic
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
sedimentary
Granite
Granite (Phaneritic Igneous Rock)
igneous
Basalt with Amygdule
Aphanitic Mafic Volcanic Rock (Basalt) with Zeolite/Quartz Infill
igneous
Biotite / Black Mica
Biotite K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Erythrite
Erythrite (Cobalt Bloom) - Co3(AsO4)2·8H2O
mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix
igneous
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Quartz Geode (Druzy Quartz)
Silicon Dioxide (SiO2)
mineral
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Milky Quartz (Water-worn Pebble)
Quartz (Silicon Dioxide) - SiO2
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Basalt with Quartz/Calcite Veins
Aphanitic Mafic Igneous Rock with Hydrothermal Veining
igneous
Quartz in Matrix (possibly with Biotite or Hornblende)
Quartz (Silicon Dioxide, SiO2) in Granitic Matrix
igneous
Milky Quartz
Quartz (SiO2) with iron staining
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Serpentinite (with Pyrite/Garnet inclusions)
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3Si2O5(OH)4
metamorphic
River Rocks (Basalt and Sedimentary Stones)
Mafic Igneous Rock (Basalt) and Clastic Sedimentary Rock
igneous and sedimentary
Pyrite
Iron Disulfide (FeS2)
mineral
Andesite Porphyry (Geological Drill Core)
Andesite Porphyry
igneous
Pink Granite
Phaneritic Felsic Igneous Rock
igneous
Porphyritic Basalt
Porphyritic Basalt (with plagioclase phenocrysts)
igneous
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Gravel or Crushed Stone
Fragmented Aggregate Stone
sedimentary or igneous fragment
Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
mineral
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Iron-Stained)
Crystalline Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Petrified Wood (Silicified Wood)
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
mineral
Ferruginous Quartz
Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3)
mineral
Petrified Wood
Silicified wood (Quartz/Chalcedony/SiO2)
sedimentary
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Clear)
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon dioxide (SiO2)
Mineral
Crinoid and Coral Fossils in Limestone
Fossiliferous Limestone with Rugosa (order) and Crinoidea (class)
sedimentary
Granite with Orthoclase and Hematite Staining
Phaneritic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)
igneous