Mineral, Organic Gemstone

Amber / Copal

Succinite (fossilized tree resin)

Geode (Unopened)

SiO2 (Quartz-filled Sedimentary Nodule)

Jasper

Silicon Dioxide (Microcrystalline Quartz, $SiO_2$)

Siltstone with Fossil Cast

Sedimentary Rock (Siltstone / Fine-grained Sandstone)

Chert Nodule / Ironstone Concretion

Microcrystalline Quartz (SiO2) with Iron Oxides

Gray River Pebble (likely Limestone or Siltstone)

Sedimentary Rock (Calcium Carbonate or Siliciclastic)

Chert (with Epidote/Quartz veining)

Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions

Sandstone (likely Fossiliferous Sandstone)

Clastic sedimentary rock (primarily SiO2)

Fossil Shark Tooth (Sand Tiger or Mackerel Shark)

Carcharias sp. or Otodus sp. replaced by Hydroxylapatite/Calcium Carbonate

Chert (Yellow/Brown Jasper)

Silicon Dioxide (SiO2)

Fossilized Dinosaur Skull (Tyrannosaurus rex)

Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Carved Sea Turtle Figurine (Aventurine / Quartz / Jasper)

Quartz variety (SiO2) / Polycrystalline Quartz Aggregate

Fossilized Coprolite

Coprolite (fossilized feces)

Petrified Wood

Silicified Wood (mainly Quartz / SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Pearl

Calcium Carbonate (Aragonite) - CaCO3

Mammoth or Mastodon Tooth Fragment

Mammuthus / Mammut molar fragment

Fossilized Shark Tooth

Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron

Baroque Pearl

Calcium Carbonate (Aragonite or Calcite) and Conchiolin

Amber (Cherry Amber)

Succinite (C10H16O)

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Chert (Jasper/Flint variant)

Microcrystalline quartz (SiO2)

Chert (and Jasper/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified wood (SiO2)

Fossilized Bone Fragment

Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)

Petrified Wood

Silicified Wood (primarily Silicon Dioxide, SiO2)

Chert (Arrowhead/Artifact Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chakra Crystal Bracelet

Mixed Mineral Assortment

Rhodochrosite

Manganese carbonate (MnCO3)

Fossilized Bone

Permineralized Vertebrate Bone

Fossilized Shark Tooth

Otodus sp. (approximate genus) / Hydroxyapatite fossil

Jasper

Silicon Dioxide (SiO2) with impurities

Amber

Amber (C10H16O)

Shark Tooth Fossil

Carcharodon / Otodus fossilized tooth (Calcium Phosphate / Hydroxyapatite)

Fish Fossil in Limestone

Lycoptera (likely) in Micritic Limestone

Petrified Wood Fragment

Silicified Wood (SiO2)

Chert (often referred to as Flint or Jasper)

Chalcedony (SiO2) - Silicon Dioxide

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Fossilized Shark Tooth

Chondrichthyes (Class)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Plume Agate

Silicon Dioxide (SiO2) - Chalcedony Variety