Quartz
Silicon Dioxide (SiO2)
Category
Browse man made object (metalwork) specimens identified by the Rock Identifier community.
Quartz
Silicon Dioxide (SiO2)
Ruby
Corundum (Al₂O₃) with Chromium (Cr)
Banded Gneiss
Gneiss (pronounced 'nice')
Schist
Schist (various mineral compositions)
Pyrite
Pyrite (FeS2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Pink Granite
Phaneritic Felsic Igneous Plutonic Rock
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)
Quartz (likely milky quartz or a stained variety)
Silicon Dioxide (SiO₂)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Banded Gneiss
Gneiss (variable mineral composition)
Fossil Coral
Coral Limestone (a type of biogenic sedimentary rock)
Labradorite (likely Black Labradorite or Larvikite)
Labradorite (Na,Ca)(Al,Si)4O8. If a rock, it is typically anorthosite, gabbro, or norite, or a variety of syenite called Larvikite if it is specifically from Larvik, Norway.
Sandstone (Pebble/Cobble)
Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)
Chert (Common Opal/Agate inclusion)
Microcrystalline Quartz (SiO2)
Diorite (Spotted or Dalmatian Stone pattern)
Diorite
Quartz (chalcedony variety) or Limestone with Quartz Veins
SiO2 (for Quartz/Chalcedony); CaCO3 (for Limestone)
Sandstone (likely Greywacke variant)
Arenite
Feldspathic Granite (likely Syenite or Granite Pegmatite)
Phaneritic Acidic Igneous Rock (KAlSi3O8 dominant with SiO2)
Garnet-Bearing Gneiss
Almandine-Garnet Gneiss
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Granite
Granite
Anthracite Coal
Anthracite (Carbon-based metamorphic rock)
Chert (Gravel Bit)
Microcrystalline silica (SiO2)
Serpentine
Serpentine-group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Granite
Granite (a plutonic igneous rock)
Granite
Granite (Main minerals: Quartz SiO2, Feldspar KAlSi3O8, Mica)
Hematite with Magnetite
Iron Oxide (Fe2O3)
Granite
Granite
Wood Beads (Palmwood/Ebony)
Various species for wood, but often refers to woods like Palmwood (e.g., Borassus flabellifer) or Ebony (Diospyros spp.) for their distinctive grain and hardness.
Ocean Jasper (Sea Jasper)
Spherulitic Chalcedony (SiO2)
Banded Agate (Brazilian Agate Slice)
Chalcedony (Silicon Dioxide / SiO2)
Mahogany Obsidian
Obsidian (SiO2 + Fe2O3)
Amber (and Citrine Quartz)
Succinite (Amber) and Silicon Dioxide (SiO2)
Basalt with Granite Inclusions (Xenoliths)
Mafic igneous rock (Basalt) with Sialic minerals
Breciated Limestone with Calcite Veins
Sedimentary Breccia (CaCO3)
Red Coral (Precious Coral)
Corallium rubrum (Calcium Carbonate, CaCO3)
Stromatolite
Biogenic Sedimentary Rock (composed predominantly of CaCO3)
Diamond
Diamond (C)
Basalt
Basalt (comprising plagioclase, pyroxene, and olivine)
General Gravel (River Rock/River Stones)
Mixed Lithic Sediments (Conglomerate Clasts)