Shale
Fissile Siliciclastic Sedimentary Rock
Category
Browse igneous and metamorphic derivative (weathered) specimens identified by the Rock Identifier community.
Shale
Fissile Siliciclastic Sedimentary Rock
Moonstone
Orthoclase (KAlSi3O8), specifically the variety showing adularescence
Orange Quartz
Silicon Dioxide (SiO2) with iron oxide inclusions
Moonstone (Feldspar variety)
Orthoclase Feldspar (KAlSi3O8)
Zircon
Zircon (ZrSiO4)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Banded Agate (Agatized Geode Slice)
Silicon Dioxide (SiO₂)
Red Granite
Phaneritic Felsic Intrusive Igneous Rock (primarily K-feldspar, Quartz, and Biotite)
Basalt with Iron Oxidation
Aphanitic Mafic Igneous Rock (composed primarily of Plagioclase and Pyroxene)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Granite Gneiss
Gneiss (derived from granitic protolith)
Basalt with Quartz/Feldspar Inclusion
Basalt (containing Silicate minerals such as SiO2 and (Ca,Na)(Al,Si)4O8)
Olivine in Basalt (Peridotite Xenolith)
Forsterite-rich Olivine (Mg2SiO4) in Aphanitic Basalt
Basalt with inclusion
Basalt (Aphanitic-Porphyritic texture)
Basalt
Mafic volcanic rock (Silicon dioxide 45-52%)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
Quartz (likely Milky Quartz or Chalcedony)
Quartz (SiO2 - Silicon Dioxide)
Moonstone
Adularia (Potassium Aluminum Silicate, KAlSi3O8)
Citrine
Citrine (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Basalt River Pebble
Basalt (Mafic Extrusive Volcanic Rock)
Granite
Phaneritic Plutonic Felsic Rock
Basalt
Basalt
Basalt
Basalt
Apache Tear (Obsidian)
Obsidian (Hydrated Amorphous Silica, SiO2 + MgO/Fe3O4)
Basalt (Vesicular/Scoriaceous)
Extrusive Mafic Volcanic Rock (Primarily Plagioclase Feldspar and Pyroxene)
Pink Granite
Phaneritic Felsic Igneous Rock
Granite (weathered/river-tumbled)
Granite (Plutonic Igneous Rock)
Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)
Quartz (SiO₂ - Silicon Dioxide)
Pink Granite (Potassium-rich)
Phaneritic Felsic Igneous Rock (K-Feldspar Granite)
Granite Cobble
Phaneritic Felsic Igneous Rock (Granite)
Kimberlite
Kimberlite (Potassic ultramafic volcanic rock)
White Quartz Pebble
Silicon Dioxide (SiO2)
Pyrite (Cube variety)
Iron Sulfide (FeS2)
Smoky Quartz
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz (Beach Pebble)
Quartz (Silicon Dioxide, SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
River Rock (Basalt)
Basalt (SiO2 range: 45-52%)
Milky Quartz
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)