Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica/Amphibole)
Category
Browse sedimentary rock (technically a microcrystalline quartz mineral aggregate) specimens identified by the Rock Identifier community.
Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica/Amphibole)
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Chert (variant of Flint)
Chert (SiO2)
Yellow Quartzite (Iron-Stained Quartzite)
Quartzite (SiO2 with Fe2O3 trace impurities)
Yellow Quartzite (Iron-Stained Quartz)
Quartzite (SiO2 with Fe-oxide impurities)
Banded Agate (likely Carnelian Agate or Sardonyx)
Agate is a common name for a microcrystalline variety of Quartz (SiO₂), specifically a form of Chalcedony.
Conglomerate
Conglomerate (clastic sedimentary rock)
Sandstone
Arenite (composed primarily of SiO2)
Quartzite (River Pebble)
SiO2 (recrystallized Quartz)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Shale
Fissile Mudstone
Sandstone (Pebble)
Sandstone (arenite, arkose, wacke depending on composition)
Carnelian
Carnelian (a variety of Chalcedony, SiO2)
Massive Quartz (Milky or Gray)
Silicon Dioxide (SiO2)
Sandstone (Quartzose type)
Arenite (primarily SiO2)
Agate (translucent pebble)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Crazy Lace Agate
Agate (Cryptocrystalline Quartz), Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Quartz (Milky or Clear variety)
Silicon Dioxide (SiO2)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
River Rock (Basalt)
Aphanitic Basaltic Rock
Sandstone (Water-worn Pebble)
Clastic Sedimentary Rock (primarily SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Yellow Quartzite (River Stone)
Quartzite (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Sandstone with Tafoni Weathering
Arenite (SiO2 based)
Milky Quartz
Silicon Dioxide (SiO2)
Ferruginous Sandstone (Gerrit)
Arenite with Iron Oxide cementation
Quartzite Pebble
Quartzite (primarily SiO2)
Conglomerate
Conglomerate (Clastic Sedimentary Rock)
Gneiss (specifically Granitic Gneiss)
Gneissic Metamorphic Rock
Sandstone
Arenite (SiO2-rich)
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Chert (Agatized Chert)
Microcrystalline Quartz (SiO2)
Fluorite and Rose Quartz
Fluorite (CaF2), Rose Quartz (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2)
Granite
Granite (Felsic Plutonic Rock)
Travertine
Calcareous Tufa (CaCO3)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)