Olivine Basalt
Mafic Volcanic Rock (rich in (Mg, Fe)2SiO4)
Category
Browse mineral in igneous rock specimens identified by the Rock Identifier community.
Olivine Basalt
Mafic Volcanic Rock (rich in (Mg, Fe)2SiO4)
Calcite
Calcium Carbonate (CaCO3)
Pink Granite
Phaneritic intrusive igneous rock with dominant Alkali Feldspar
Wishing Stone (Basalt with Quartz Vein)
Basalt containing a microcrystalline quartz (SiO2) or calcite vein
White Quartz Pebble
Silicon Dioxide (SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock)
Basalt River Rock
Basalt (Aphanitic Mafic Igneous Rock)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Rhodonite
Rhodonite (MnSiO3)
Pyrite in Matrix (often with Chalcopyrite)
Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)
Milky Quartz
Silicon Dioxide (SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Agate
Silicon Dioxide (SiO2) - Chalcedony variety
Schist
N/A (a rock type, not a mineral formula)
Yellow Quartz (Citrine or Iron-Stained Quartz)
Silicon Dioxide (SiO2)
Granodiorite Pebble
Granodiorite
Quartz Druzy (on Calcedony/Quartz base)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Granite
Granite (a felsic intrusive igneous rock)
Basalt with Vesicular Texture (Beach Cobble)
Vesicular Basalt (Aphanitic Igneous Rock)
Basalt with Quartz/Calcite Inclusions
Mafic Volcanic Rock (Fe-Mg silicate rich)
Quartz (likely Rose Quartz or Milky Quartz based on color)
Quartz (SiO2 - Silicon Dioxide)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Dragon Blood Jasper
Epidote-containing Quartz Chalcedony (SiO2 with Ca2(Al, Fe)3(SiO4)3(OH))
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Basalt with Desert Varnish
Mafic Igneous Rock with Ferromanganese Coating
Gneiss (Metamorphic Rock)
Gneiss (variable mineral formula primarily containing Quartz, Feldspar, and Mica)
Granitic Pegmatite
Pegmatite containing Quartz, Feldspar, and Muscovite mica
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Carnelian Agate
Carnelian (SiO2 with iron oxide impurities)
Granite
Granite (Mainly Quartz, Feldspar, and Mica)
Quartz (Milky and Bull Quartz)
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
Clear Quartz Crystal
Quartz (Silicon Dioxide, SiO2)
Quartz (Rose or Clear variety)
Silicon Dioxide (SiO2)
Granite
Granite (Phaneritic intrusive igneous rock)
Granitic Gneiss
Gneiss (Metamorphic rock of granitic composition)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)