Chalcedony (likely agate/chert variety)
Microcrystalline quartz, SiO₂
mineral
Category
Man Made Object (Simulant)
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Polished red jasper beads
Jasper, microcrystalline quartz (SiO₂), colored mainly by iron oxides
mineral
Tumbled amethyst
Quartz, purple variety — SiO₂, colored mainly by iron impurities and irradiation
gemstone
Botryoidal iron-rich jasper
Ferruginous jasper/chalcedony, primarily microcrystalline quartz (SiO₂) with iron oxides and hydroxides
mineral
Polished black stone, likely black obsidian
Obsidian (volcanic glass; mainly SiO₂)
igneous
Tumbled jasper (likely picture jasper or iron-rich jasper)
Microcrystalline quartz/chalcedony, SiO₂, colored by iron oxides
sedimentary
Polished tiger’s-eye cabochon (probable)
Quartz variety, SiO₂, with fibrous riebeckite/crocidolite-derived inclusions
metamorphic
Tumbled green aventurine (likely)
Quartz (SiO₂) with fuchsite or other green mica inclusions
mineral
Black Obsidian
Volcanic Glass (felsic)
igneous
Red Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
sedimentary
Agate
Silicon dioxide (Chalcedony), SiO2
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Green Aventurine
Quartz with Fuchsite inclusions (SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Septarian Nodule
Septarian Concretion (Calcite, Aragonite, and Limestone)
sedimentary
Obsidian
Volcanic Glass
igneous
Labradorite
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
mineral
Yellow Jasper
Silicon Dioxide (SiO2) with impurities, microcrystalline quartz
sedimentary
Carnelian
Silicon Dioxide (Chalcedony variety), SiO2
gemstone
Quartz
Silicon Dioxide (SiO2)
mineral
Green Aventurine
Quartz with Fuchsite inclusions (SiO2)
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified wood (Quartz / Chalcedonized wood, SiO2)
sedimentary
Malachite and Cuprite on Host Rock
Cu2CO3(OH)2 (Malachite) and Cu2O (Cuprite)
mineral
Leopard Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Clear Quartz (Cut/Faceted Gemstone)
Silicon Dioxide (SiO2)
gemstone
Blue Tiger's Eye (Hawk's Eye)
Pseudomorph of Quartz after Crocidolite (SiO2)
gemstone
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions) - SiO2
mineral
Obsidian and Fossilized Shark Tooth
Obsidian (Volcanic Glass) and Otodus sp. (Fossilized shark tooth)
igneous and fossil
Fuchsite (Chrome Mica)
K(Al,Cr)2(AlSi3O10)(OH)2
mineral
Lapis Lazuli
Lapis lazuli (Complex rock consisting mainly of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
metamorphic
Carnelian
Carnelian (SiO2 with Fe2O3 impurities)
mineral
Black Onyx or Dyed Agate Node
Cryptocrystalline Quartz (SiO2)
mineral
Amber
Fossilized tree resin
gemstone
Amber
Succinite (organic mineraloid); Chemical formula: C10H16O
mineral
Labradorite
Labradorite ((Ca, Na)(Al, Si)4O8)
mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Lapis Lazuli
Lazurite-rich metamorphic rock; (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2
metamorphic
Banded Agate (specifically Carnelian Agate)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Greenstone (Greenschist)
Greenschist facies rock (containing chlorite, actinolite, and epidote)
metamorphic
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary