Likely bituminous coal
Coal, predominantly carbon-rich organic matter; exact rank cannot be confirmed from the image
sedimentary
Category
Organic (Biological Organism)
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Fossilized wood, likely silicified petrified wood
Silicified wood (fossil wood; commonly quartz/chalcedony replacing organic tissue)
fossil
Polished jasper, likely orbicular or brecciated jasper
Jasper: microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides and other inclusions
mineral
Fossilized bone fragment
Petrified bone, mineral-replaced vertebrate bone; exact taxon indeterminate
fossil
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
sedimentary
Ironstone Concretion
Siderite or Hematite Concretion
sedimentary
Petrified Wood
Silicified wood (primarily SiO2)
fossil
Fossiliferous Limestone (Coquina / Shell Limestone)
Bioclastic Limestone (CaCO3)
sedimentary
Petrified Wood
Siliconized Wood (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
sedimentary
Petrified Wood
Silicified Wood (primarily Silicon Dioxide, SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Hag Stone (Chert/Flint with natural perforation)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Shell Cameo (Sardonyx Shell)
Cassis madagascariensis (Sardonyx shell)
mineral (biogenic silica/calcium carbonate substrate)
Polished amber
Amber (fossilized plant resin; primarily organic polymerized terpenes)
gemstone
Polished fossil coral
Agatized or silicified coral, commonly fossilized stony coral (Scleractinia); exact genus cannot be determined from the image
fossil
Fossilized stromatolite or laminated microbial mat
Layered carbonate/chert fossil; exact taxon indeterminate from the image
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossilized wood (petrified wood)
Silicified fossil wood; commonly quartz (SiO₂) replacing wood tissues
fossil
Petrified Wood
Silicified Wood (primarily SiO2)
fossil
Green Slate or Metamorphic Rock with Moss/Lichen
Metamorphic rock / Phyllite or Slate variant
metamorphic
Fossiliferous Limestone
Fossiliferous Limestone (Sedimentary Rock)
fossil
Orthoceras Fossil Limestone
Orthoceras (extinct Cephalopod fossil) in Matrix
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
sedimentary
Chert Nodules in Limestone
Cryptocrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
sedimentary
Amber (fossilized tree resin)
Succinite; organic resin composed mainly of polymerized terpenoids
fossil
Pearl
Nacre (primarily aragonite, CaCO₃, in an organic conchiolin matrix)
gemstone
Petrified Wood
Silicified wood (Quartz / Chalcedony replacement of organic cellulose)
fossil
Petrified Wood (Black / Carbonized)
Silicon Dioxide (Quartz/Chalcedony replacing Organic Matter)
fossil
Petrified Wood
Silicified wood (Quartz replacement of organic wood structure)
fossil
Petrified Wood
Silicified Wood (Permineralized organic matter, głównie $SiO_2$)
fossil
Flint with Fossil Inclusion
Cryptocrystalline quartz (SiO2) enclosing fossilized organic remains
sedimentary
Blue Quartzite (Dyed)
Metamorphosed Quartz-rich Sandstone (SiO2 with organic dye)
metamorphic
Pearl
Calcium carbonate (CaCO3) + organic conchiolin (Biogenic Mineral)
mineral
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and organic impurities
sedimentary
Dyed Blue Agate (Dragon Vein Agate)
Silicon Dioxide (SiO2) with artificial cobalt/organic dyes
mineral
Dinosaur Bone (Gembone)
Silicified Dinosaur Bone (SiO2 replacing organic tissue)
sedimentary
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3)
sedimentary
Shale
Laminated Fissile Pelite
sedimentary