Tumbled brown agate or jasper
Microcrystalline quartz, SiO₂ (likely chalcedony/agate with iron oxides)
mineral
Category
Anthropogenic (Man Made Material Processed By Nature)
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Clear quartz sphere
Quartz (silicon dioxide, SiO₂), likely rock crystal or low-grade milky quartz
mineral
Likely basalt (possibly a dark beach pebble)
Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with olivine
igneous
Sandstone
Arenite (Sandstone)
sedimentary
Sandstone
Arenite
sedimentary
Lazulite
Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2
mineral
Black Onyx
Silicon Dioxide (SiO2)
mineral
Pink Dyed Agate (Pink Agate Slice)
Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz
mineral
Pink quartz-rich stone, likely rose quartz
Rose quartz; quartz, SiO₂, commonly colored by trace elements and microscopic inclusions
mineral
Fossilized tooth, likely mammalian molar
Indeterminate Mammalia; mineralized dentine and enamel
fossil
Orange Quartz (Citrine Quartz)
Silicon Dioxide (SiO2) with iron impurities
mineral
Granite
Intrusive igneous rock composed mainly of quartz, alkali feldspar, and plagioclase
igneous
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Cubic Zirconia
Zirconium dioxide (ZrO2)
mineralogical simulant / gemstone
Quartz (Variety: Citrine or Tumbled Chalcedony)
Silicon Dioxide (SiO2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Bituminous coal
Coal; predominantly vitrinite and inertinite macerals composed chiefly of carbon, hydrogen, oxygen, nitrogen, and sulfur
sedimentary
Tumbled banded jasper, likely brecciated jasper
Microcrystalline quartz (SiO₂) with iron-oxide and clay inclusions
mineral
Red cabochon gemstone, likely carnelian
Carnelian: orange-red chalcedony, microcrystalline quartz (SiO₂)
gemstone
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
mineral
Chert (or potentially massive Quartz/Quartzite)
SiO2 (Silicon Dioxide)
sedimentary (if chert) / metamorphic (if quartzite)
Asphalt Conglomerate
Artificial Bituminous Conglomerate
sedimentary
Porphyritic granite or granodiorite
Coarse-grained plutonic rock composed mainly of quartz (SiO₂), feldspar, and mica/amphibole
igneous
Quartz-rich rock, possibly milky quartz or quartzite
Quartz (SiO₂), potentially quartzite if the grains are fused
mineral
Iron-rich chert or jasper
Microcrystalline quartz (SiO₂), colored by hematite/goethite inclusions
sedimentary
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Polished dark stone, likely basalt
Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine
igneous
Quartz
Silicon Dioxide (SiO2)
mineral
Blue Agate (Dyed)
Silicon Dioxide (SiO2) with artificial pigment
mineral
Diamond
Carbon (C)
gemstone
Corundum (Pink Sapphire / Ruby)
Al2O3 (Aluminum Oxide)
mineral
Diamond (in a jewelry setting)
Carbon (C)
mineral
Lemon Quartz (or Yellow Calcite)
Silicon Dioxide (SiO2) / Calcium Carbonate (CaCO3)
mineral
Sandstone
Arenite (SiO2 primarily)
sedimentary
Sandstone (Water-worn pebble)
Arenite (primarily SiO2)
sedimentary
Polished red jasper
Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides
mineral
Chert
Chert (Microcrystalline Silica, SiO2)
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Weathered quartz-rich rock, possibly chert or milky quartz
Mostly microcrystalline or crystalline quartz (SiO₂), identification uncertain from photograph
mineral
Tumbled dark gray stone, likely basalt
Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine
igneous
Pink Tourmaline (Rubellite)
Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4)
mineral
Unidentified gray stone
Likely quartz-rich stone; exact identification is not possible from the image
mineral