Likely milky quartz fragment
Quartz (SiO₂)
mineral
Category
Man Made
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Milky quartz (rough fragment)
Quartz, silicon dioxide (SiO₂)
mineral
Turquoise ring
Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O; the setting appears to be silver-colored metal
gemstone
Polished hematite (specimen identification uncertain)
Hematite, α-Fe₂O₃
mineral
Polished goniatite fossil limestone
Goniatite-bearing Devonian–Carboniferous limestone; fossil cephalopod shells (Goniatitida) in calcite-rich matrix
fossil
Polished amethyst-bearing quartz
Quartz, SiO₂; purple coloration from irradiation and trace iron
mineral
Polished, carved gemstone (possibly dyed agate or glass-like material)
Unconfirmed from the image; no specific mineral can be identified reliably
gemstone
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Obsidian
Volcanic Glass (70% or more SiO2)
igneous
Pumice
Pumice (Vesicular volcanic glass)
Igneous
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Diamond
Carbon (C)
mineral
Blue-stone and diamond ring
Blue stone is possibly blue sapphire (corundum, Al₂O₃); surrounding stones appear to be diamonds (carbon, C).
gemstone
Red cabochon gemstone ring (likely glass or synthetic stone)
Undetermined; the image does not establish a natural mineral identity
gemstone
Flint
SiO2 (Microcrystalline Quartz)
sedimentary
Quartzite
Metamorphic Quartz Arenite
metamorphic
Quartzite
Metamorphic Quartz Arenite
metamorphic
Quartzite
Metamorphic Quartz Rock (SiO2)
metamorphic
Mica (likely biotite-rich mica aggregate)
Biotite, a potassium–iron–magnesium mica; approximate formula K(Mg,Fe)₃AlSi₃O₁₀(F,OH)₂
mineral
Rounded gray pebble, likely quartzite
Quartzite (predominantly crystalline quartz, SiO₂); identification is tentative from the image
metamorphic
Kyanite
Aluminium Silicate, Al2SiO5
mineral
Crinoid stem fossil
Crinoidea
fossil
Sandstone Concretion
Sedimentary concretion
Sedimentary
Slate
Metamorphic Pelitic Rock
metamorphic
Blue Lace Agate
Chalcedony (SiO2) with trace inclusions
mineral
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
sedimentary
Polished hematite
Hematite, iron(III) oxide (α-Fe₂O₃)
mineral
Tumbled feldspar, likely orthoclase
Potassium feldspar (KAlSi₃O₈), likely orthoclase
mineral
Orange tumbled feldspar, likely sunstone
Probably potassium feldspar (orthoclase or microcline); identification is uncertain from the image
mineral
Polished stromatolite (likely fossilized microbial mat)
Fossil stromatolite; chiefly microcrystalline quartz (SiO₂), commonly replacing carbonate
fossil
Dark green cabochon gemstone ring
Unknown; possibly green onyx (cryptocrystalline quartz, SiO₂) or another green gem
gemstone
Engineered Quartz Stone
Agglomerated Quartz (SiO2 + Polymer Resin)
mineral-based composite
Sandstone
Arenite
sedimentary
Exposed aggregate concrete (stone-chip surface)
Portland-cement concrete containing natural aggregate; not a natural rock
sedimentary
Laterite
Fe2O3 and Al2O3 rich residual rock
sedimentary
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Quartzite
Metamorphic Quartz Arenite
metamorphic
Chert
Silicon Dioxide (SiO2)
sedimentary
Green jasper (possibly dyed or coated)
Microcrystalline quartz, SiO₂; jasper is an opaque variety of chalcedony
mineral
Muscovite mica
Muscovite, KAl₂(AlSi₃O₁₀)(OH)₂
mineral
Polished blue chalcedony (possibly agate)
Microcrystalline quartz, SiO₂; chalcedony, potentially banded agate
mineral
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary