Milky Quartz with Dendritic Inclusions
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
mineral
Category
Organic Gemstone (Fossilized Resin)
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Crinoid Fossil in Chert
Crinoid (Class Crinoidea) in Microcrystalline Quartz (SiO2)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Synthetic Resin / Plastic Figurine
Synthetic Polymer (Copolymer of Polyethylene or Resin)
Mineraloid-like Synthetic Material
Chert / Flint
Silicon dioxide (SiO2)
sedimentary
Dyed or treated turquoise-like tumbled stone
Likely turquoise (CuAl₆(PO₄)₄(OH)₈·4H₂O), though blue-green magnesite or howlite imitation is possible
mineral
Fossil Coral
Hexagonaria or Rugose Coral (Fossilized Calcium Carbonate / Silica)
fossil
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxide
mineral
Fossil Shark Tooth
Carcharodon carcharias (modern/recent) or similar Lamniform fossil
fossil
Petoskey Stone
Hexagonaria percarinata
sedimentary
Chert Cobble with Crinoid Fossil
Silica (SiO2) with Crinoid ossicle
sedimentary
Fossilized Rugose Coral (Petoskey Stone type)
Hexagonaria percarinata (Order: Rugosa)
sedimentary
Sphalerite with Galena
Zinc Sulfide ((Zn,Fe)S) and Lead Sulfide (PbS)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
metamorphic
Freshwater Pearl
Calcium Carbonate (CaCO3) in the form of Aragonite and Calcite
gemstone
River Jasper (Chert/Chalcedony)
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary
Fossilized Rugose Coral (Horn Coral)
Order Rugosa
fossil
Mammoth Tooth Fragment
Mammuthus primigenius (fossilized dentin and enamel)
sedimentary
Fossilized Rugose Coral (Horn Coral)
Order Rugosa (Calcium Carbonate - CaCO3)
sedimentary
Quartzite Cobble
Quartzite (SiO2)
metamorphic
Petoskey Stone
Hexagonaria percarinata
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
sedimentary
Carved red jasper bead (likely ceramic imitation)
Jasper, microcrystalline quartz (SiO₂); exact material uncertain from the image
mineral
Travertine
Travertine (form of massive calcium carbonate, CaCO3)
sedimentary
Sandstone (Quartz Sandstone)
Arenite (primarily SiO2)
sedimentary
Fossil Coral (Petoskey Stone / Rugose Coral)
Hexagonaria percarinata (or similar fossilized rugose/tabulate coral)
fossil
Chert (Flint Nodules)
Silicon Dioxide (SiO2)
sedimentary
Polished tree agate (likely)
Chalcedony (microcrystalline SiO₂) with green dendritic/inclusion minerals
mineral
Sandstone
Sedimentary Rock (Quartz arenite)
sedimentary
Sandstone
Sedimentary Rock (Quartz arenite)
sedimentary
Bivalve Fossil (Clam)
Class Bivalvia (e.g., Exogyra or Gryphaea species)
fossil
Coral Fossil
Anthozoa (Scleractinia)
fossil
Crinoid Fossil in Limestone
Crinoidea (Phylum Echinodermata) in Calcite Matrix (CaCO3)
fossil
Sandstone Pebble
Arenite (SiO2 complex)
sedimentary
Sandstone
Arenite (SiO2 principal)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Kambaba Jasper
Stromatolite / Fossilized Algae (Rhyolitic structure)
sedimentary
Quartz Vein in Pelite (Metamorphic Rock)
Hydrothermal Quartz Veining in Metasedimentary Rock (SiO2)
metamorphic
Ironstone Concretion (Pot Stone)
Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)
sedimentary
Sandstone (Wonderstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary