Milky Quartz
Silicon Dioxide (SiO2)
Category
Browse sedimentary (base), then artificial specimens identified by the Rock Identifier community.
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Porphyritic Andesite
Andesite (Porphyry)
Iron Slag
Ferrous Slag (complex silicate and oxide byproduct)
Slag
Ferrous slag (by-product of iron smelting)
Granite (with Quartz and Mica)
Phaneritic Felsic Igneous Rock
Basalt (River Stone)
Aphanitic Mafic Igneous Rock
Basalt with Quartz Vein
Basalt (SiO2 vein inclusion)
Anthracite Coal
Anthracite (Carbon-based metamorphic rock)
Schist
Schist (Crystalline metamorphic rock)
Sunstone
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
Smoky Quartz in Matrix (Pegmatite)
Silicon Dioxide (SiO2) with Potassium Feldspar and Biotite mica
Heat-Treated Amethyst (Commercial Citrine)
Silicon Dioxide (SiO2) - Macro-crystalline Quartz
Blue Aventurine
Silicon Dioxide (SiO2) with inclusions of Dumortierite
Diamond
Native Carbon (C)
Gold Nugget / Flake
Native Gold (Au)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Quartzite
Quartzite (mostly SiO2)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Pink Granite (Fragment)
Pink Granite (dominated by Potassium Feldspar: KAlSi3O8)
Basalt
Basalt (Igneous Volcanic Rock)
Basalt
Basalt
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
Granite
Intrusive Phaneritic Felsic Igneous Rock
Granite
Granite (composed primarily of Quartz (SiO2), Alkali Feldspar, and Plagioclase)
Pink Granite (Potassium-rich Granite)
Phaneritic Felsic Igneous Rock (primarily SiO2, Al2O3, K2O)
Quartzite (Water-worn Cobble)
Quartzite (Composition: 90%+ SiO2)
Basalt
Mafic Volcanic Rock (primarily Plagioclase and Pyroxene)
Basalt
Basalt (Mafic volcanic rock)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Porphyry
Porphyritic Rhyolite or Andesite
Basalt
Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)
Diorite
Diorite (Intermediate intrusive igneous rock)
Coarse-grained Granite (Quartz and Feldspar dominated)
Granitoid (KAlSi3O8 – NaAlSi3O3 – CaAl2Si2O8 – SiO2)
Dolerite (Diabase)
Dolerite / Diabase
Diorite
Diorite (Intermediate intrusive igneous rock)
Diorite (River Cobble)
Intermediate Phaneritic Plutonic Rock
Diorite
Diorite (Intermediate intrusive igneous rock)
Basalt with Plagioclase Phenocrysts (Porphyritic Basalt)
Mafic volcanic rock (formula primarily (Mg, Fe)2SiO4 and CaAl2Si2O8)
Red Rhyolite Porphyry
Rhyolite (Porphyritic texture)
Basalt
Basalt (Mafic volcanic rock)
Basalt with Quartz/Calcite Vein
Amygdaloidal Basalt (matrix) with Mineral Vein filling