Blue glass-like bead or gemstone keychain ornament
Indeterminate; likely cobalt-blue glass or synthetic blue spinel, not identifiable as a natural mineral from the image
gemstone
Category
Man Made Material (Constructed)
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Limestone
Calcium Carbonate (CaCO3)
sedimentary
Limestone
Calcite-rich sedimentary rock (CaCO3)
sedimentary
Chert (likely flint)
Microcrystalline quartz, SiO₂
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Blue Goldstone
Synthetic Aventurescent Glass (Cobalt-doped soda-lime glass)
man-made glass
Blue Goldstone
Aventurine Glass (SiO2 with Cobalt/Copper inclusions)
man-made glass
Slate
Metamorphic Pelitic Rock
metamorphic
N/A - Man-made object (Jewelry Chain)
Antiqued or Oxidized Metal Chain (often Steel or Brass)
Mineral (processed metal)
Man-made Jewelry Charm (Enameled Metal)
Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.
Synthetic / Manufactured Artifact
Marble
Recrystallized Calcite / Dolomite (CaCO3)
metamorphic
Marble
Recrystallized Carbonate Rock (CaCO3)
metamorphic
Diamond
Native Carbon (C)
mineral
Polished amethyst-bearing quartz
Quartz, SiO₂; purple coloration from irradiation and trace iron
mineral
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
mineraloid
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Granite Pebble
Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)
igneous
Blue chalcedony cabochon (likely)
Chalcedony, microcrystalline SiO₂; possibly blue agate or common opal, which cannot be distinguished confidently from the image
mineral
Chert (White Chert/Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Marble
Recrystallized Calcite (CaCO3) Rock
metamorphic
Flint (gray chert)
Microcrystalline quartz (SiO₂), a variety of chert
sedimentary
Flint (chert)
Microcrystalline quartz (SiO₂), a variety of chert
sedimentary
Coquina
Bioclastic Limestone
sedimentary
Likely flint (chert) fragment
Chert, microcrystalline quartz (SiO₂)
sedimentary
Ruby in Matrix
Corundum (Al2O3)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
White Marble
Recrystallized Calcite (CaCO3)
metamorphic
Diamond
Carbon (C)
mineral
Sandstone
Arenite
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Red agate bead (likely dyed or treated)
Agate, a microcrystalline variety of quartz; SiO₂
gemstone
Red-orange sunstone (likely aventurine feldspar) bead bracelet
Feldspar, commonly oligoclase or labradorite with copper inclusions; composition varies by source
mineral
Slate
Metamorphic Pelitic Rock
metamorphic
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Chert or Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Exposed aggregate concrete (stone-chip surface)
Portland-cement concrete containing natural aggregate; not a natural rock
sedimentary
Fossiliferous Limestone
CaCO3 (principally Calcite or Aragonite)
sedimentary
Engraved purple stone cabochon, possibly amethyst
Unconfirmed; if amethyst, quartz (SiO₂)
gemstone
Blue chalcedony cabochon (probable)
Chalcedony, a cryptocrystalline variety of quartz; silicon dioxide, SiO₂
gemstone
Polished stromatolite (likely fossilized microbial mat)
Fossil stromatolite; chiefly microcrystalline quartz (SiO₂), commonly replacing carbonate
fossil
Tiger Shark Fossil Tooth
Galeocerdo cuvier (fossilized)
sedimentary