Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
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Green Fluorite (likely synthetic or heat-treated for jewelry)
Calcium Fluoride (CaF2)
mineral
Epidote-bearing Rock
Epidote / Silicate mineral aggregate
metamorphic
Pyromorphite
Pyromorphite (Pb5(PO4)3Cl)
mineral
Fluorite (Fluorescent)
Calcium Fluoride (CaF2)
mineral
Pegmatite
Igneous Pegmatite
igneous
Herkimer Diamond
Double-terminated Quartz (Silicon Dioxide, SiO2)
mineral
Banded gneiss
Gneiss, commonly quartz–feldspar–biotite gneiss
metamorphic
Weathered granite or granitic gneiss
Granite: quartz + feldspar + biotite/hornblende; possible gneissic equivalent
igneous
Banded Gneiss
Gneiss
metamorphic
Diorite (River Rock/Cobble)
Intermediate Plutonic Igneous Rock (Diorite)
igneous
Gneiss
Gneiss (High-grade regional metamorphic rock)
Metamorphic
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Diorite
Phaneritic intermediate plutonic rock
igneous
Iron-Stained Quartz Pebble
Quartz (Silicon Dioxide, SiO2) with Iron Oxide Inclusion/Staining
mineral
Mammoth molar tooth fossil
Mammuthus sp.; fossilized molar with enamel plates and dentine
fossil
Ammonite fossil
Ammonoidea; likely a polished small ammonite, possibly Cleoniceras
fossil
Banded metamorphic rock, likely gneiss
Biotite–quartz–feldspar gneiss, possibly migmatitic
metamorphic
Weathered quartz-bearing rock, possibly granite or gneiss
Indeterminate; likely quartz–feldspar–mica aggregate, possibly granitic gneiss
igneous
Shark Tooth Fossil
Chondrichthyes fossil
fossil
Gneiss
Banded orthogneiss or paragneiss, typically quartz–feldspar–mica bearing
metamorphic
Turtle Stone / Septarian Nodule (Fragment)
Septarian Concretion (Calcite, Aragonite, and Limestone)
sedimentary
Limonite (Ironstone)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
mineral
Granite
Phaneritic plutonic rock (Quartz, Alkali Feldspar, and Plagioclase)
igneous
Green serpentine or nephrite-like stone
Serpentinite, chiefly serpentine-group minerals; exact identification would require testing
metamorphic
Polished serpentine (likely bowenite)
Serpentine-group minerals, chiefly antigorite; bowenite is a nickel-rich translucent variety
metamorphic
Diamond
Carbon (C)
gemstone
Native Copper
Native Copper (Cu)
mineral
Iron-rich mineral fragment, possibly limonite/goethite
Limonite (hydrated iron oxides; commonly goethite, FeO(OH), with hematite)
mineral
Shattuckite (Blue Quartz/Jasper Matrix)
Shattuckite (Copper Silicate Hydroxide - Cu5(SiO3)4(OH)2)
mineral
Amygdaloidal Basalt with Secondary Minerals
Basalt containing secondary mineralization (likely Chlorite, Celadonite, or Zeolites)
igneous
Carved Gemstone Mushroom
Quartz / Feldspar composite (Carved lapidary art)
gemstone
Unknown dark mineral fragment
Indeterminate; possibly a dark silicate mineral or slag-like geological fragment
mineral
Likely weathered metallic mineral or slag fragment
Indeterminate; possibly iron-rich sulfide/oxide material or industrial slag
mineral
Bauxite
Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)
sedimentary
Felsic Drill Core (likely Gneiss or Granite)
Felsic Metamorphic Rock (Gneissic profile)
metamorphic
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Kunzite
Spodumene (LiAlSi2O6)
mineral
Epidote with Magnetite/Hematite inclusions
Epidote (Ca2(Al2,Fe3+)(SiO4)3(OH)) with Iron Oxides
mineral
Purpurite
Manganese Iron Phosphate, Mn3+(PO4)
mineral
Chrysocolla
Cu2-xAlx(H2O)n(H2Si2O5)5 · nH2O (Hydrated copper aluminum silicate)
mineral
Druzy Quartz on Ironstone
Silicon Dioxide (SiO2) on Limonitic Ironstone
mineral