Banded Calcite (commonly traded as Green Onyx / Travertine Onyx)
Calcite (CaCO3) / Travertine
sedimentary
Category
Mineral Based Composite
Browse mineral based composite specimens identified by the Rock Identifier community.
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Blue turquoise cabochon
Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O; likely dyed or stabilized, flower-shaped polished piece
gemstone
Red Sandstone
Arenite (with Iron Oxide / Hematite cementation)
sedimentary
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Red Sandstone
Arenite (composed primarily of Quartz and Iron Oxide)
sedimentary
Sandstone
Sandstone (Quartz-rich Arenite / SiO2)
sedimentary
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Carved jade pendant (likely jadeite)
Jadeite, NaAlSi₂O₆; the image does not allow definitive distinction from nephrite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂
gemstone
Jasper (likely a variety of Yellow or Mustard Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary (chemically precipitated mineral)
Pebble
Lithic fragment
sedimentary
Sandstone
Arenite (composed primarily of Quartz: SiO2)
sedimentary
Diamond Drill Core (Greenschist and Quartzite)
Chlorite Schist / Meta-quartzite (Metamorphic Rock Core Sample)
metamorphic
Peach Aventurine
Silicon Dioxide (SiO2) with Hematite/Goethite inclusions
mineral
Kyanite
Kyanite (Al2SiO5)
mineral
Weathered granite
Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica
igneous
Green Fluorite
Calcium Fluoride (CaF2)
mineral
River Cobble (Quartzite or Gneiss)
Metamorphic crystalline rock (predominantly SiO2 based)
metamorphic
Gold
Native Gold (Au)
mineral
Gold Nugget
Native Gold (Au)
mineral
Gold Nugget
Native Gold (Au)
mineral
Kyanite (in Schist Matrix)
Kyanite (Al2SiO5)
metamorphic
Iron-stained quartz-rich rock fragments
Likely quartz (SiO₂) with limonite/goethite iron oxides; possibly quartzite or silicified rock
mineral
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
sedimentary
Sandstone (with Limonite/Iron Staining)
Arenite (SiO2 based) with FeO(OH) staining
sedimentary
Milky quartz-bearing rock, possibly quartzite
Quartz (SiO₂), likely in a quartzite or quartz-rich metamorphic matrix
metamorphic
Schalenblende
Sphalerite with Wurtzite, Galena, and Marcasite/Pyrite
mineral
Amethyst
Quartz (Silicon Dioxide with iron impurities), SiO2
mineral
Limonite
Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O
mineral
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
sedimentary
Tumbled greenish chalcedony or serpentine pebble
Likely microcrystalline quartz (chalcedony, SiO₂) or serpentine-group mineral; exact identification requires testing
mineral
Milky quartz
Quartz (silicon dioxide, SiO₂)
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Raw turquoise-bearing rock
Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O, likely in a limonite/matrix host
mineral
Opalite (likely man-made opalescent glass)
Opalite; not a true mineral, typically synthetic opalescent glass (silica-based)
mineral
Brown Chert
Cryptocrystalline Silica (SiO2)
sedimentary
Sandstone (with Laminations)
Clastic sedimentary rock (primarily Quartz-based)
sedimentary
Tourmalinated Quartz
Quartz (SiO2) with included Tourmaline (complex borosilicate)
Mineral composite
Pink Feldspar / Rhodochrosite (Tumbled Pink Quartzite)
SiO2 (Quartz) / KAlSi3O8 (Potassium Feldspar)
mineral
Slate
Foliated Metamorphic Rock (primarily composed of quartz, illite, chlorite, and micas)
metamorphic
Milky Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
mineral
Sandstone (Ferruginous)
Sandstone (mainly SiO2 with Fe2O3 staining)
sedimentary
Quartzite (or Quartz Slab)
SiO2 (Silicon Dioxide)
metamorphic