Chert (with Epidote/Quartz veining)
Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions
sedimentary
Category
Organic Gemstone (Not A Mineral)
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Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Pyrite (Fool's Gold) in Matrix
Iron Sulfide (FeS2)
mineral
Petrified Wood
Silicified Wood (primarily Quartz/SiO2)
mineral
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Banded Chert / Flint Pebble
Microcrystalline Quartz (SiO2)
sedimentary
Moss Agate
Agate (Silicon Dioxide, SiO2) with dendritic inclusions
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
sedimentary
Fossilized Coprolite
Coprolite (fossilized feces)
sedimentary
Chert (Jasper/Flint variant)
Microcrystalline quartz (SiO2)
sedimentary
Polished blue-green chalcedony (likely moss or dendritic agate)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
mineral
Moss Agate (Crescent Moon Shape)
Silicon Dioxide (SiO2) with iron/manganese inclusions
mineral
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxide
mineral
Moss Agate
Silicon Dioxide (SiO2) with Manganese or Iron Oxide inclusions
mineral
Amber
Succinite (Fossilized Tree Resin) - C10H16O
mineral
Petrified Wood
Silicified Wood (mainly Quartz / SiO2)
fossil
Chert (and Jasper/Chalcedony variety)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Dinosaur Bone
Agatized Dinosaur Bone
sedimentary/fossil
Ironstone Concretion (Iron-rich Mudstone)
Siderite / Geothite concretion (FeCO3 / FeO(OH))
sedimentary
Fossilized Shark Tooth (Fragment)
Elasmobranchii gen. indet.
fossil
Mammoth or Mastodon Tooth Fragment
Mammuthus / Mammut molar fragment
fossil
Fossilized Shark Tooth
Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron
sedimentary
Moss Agate
Silicon Dioxide with inclusions (SiO2)
mineral
Red Sandstone
Sandstone (Quartz Arenite / Arkose with Hematite cement)
sedimentary
Ironstone Concretion
Ironstone (primarily Siderite or Limonite)
sedimentary
Black Shale
Argillaceous Chert/Shale
sedimentary
Jasper
Silicon dioxide (SiO2)
sedimentary
Bivalve Fossil (Internal Mold/Steinkern)
Class Bivalvia (Fossilized Mold)
sedimentary
Fossilized Shark Tooth
Chondrichthyes (Class) fossil
fossil
Dyed Coral
Calcium carbonate (CaCO3) - Calcite or Aragonite with dye
organic gemstone
Amber (Butterscotch/Egg Yolk Variety)
Succinite (Approx. C10H16O)
Organic Gemstone
Chert (Arrowhead/Artifact Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Yellow Quartz
Silicon Dioxide (SiO2)
mineral
Raw Citrine Quartz
Silicon Dioxide (SiO2)
mineral
Amazonite
Microcline feldspar (KAlSi3O8)
mineral
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2
mineral
Emerald in Host Rock
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Citrine
SiO2 (Silicon Dioxide)
mineral
Fossil Shark Tooth (Sand Tiger or Mackerel Shark)
Carcharias sp. or Otodus sp. replaced by Hydroxylapatite/Calcium Carbonate
sedimentary