Mineral Like Byproduct (Technogenic)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Dendritic Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Granite

Granite

Pink Dyed Agate (Pink Agate Slice)

Silicon Dioxide (SiO2) - Chalcedony / Cryptocrystalline Quartz

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Sandstone

Arenite

Quartz Geode

Silicon Dioxide (SiO2)

Obsidian

Obsidian (volcanic glass; primarily SiO2)

Obsidian

Volcanic Glass (Amorphous Silica)

Sandstone (likely Arkosic)

Arenite (SiO2 based)

Sandstone (likely Arkose or Lithic)

Clastic sedimentary rock (SiO2 + impurities)

Sapphirine in Matrix

Sapphirine (Mg,Al)8(Al,Si)6O20

Greenstone

Greenschist-facies basaltic rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

Septarian Pebble

Septarian nodule / Concretion

Malachite

Copper Carbonate Hydroxide (Cu2CO3(OH)2)

Schist

Schist (Crystalline Metamorphic Rock)

Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles

Mixed gemstones (primarily Silicon Dioxide - SiO2)

Obsidian

Obsidian (Volcanic Glass)

Lepidolite

K(Li,Al)3(Al,Si,Rb,Cs)4O10(F,OH)2

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Pink Lepidolite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite/Iron inclusions

Strawberry Quartz (Red Aventurine)

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Garnet (Almandine)

Almandine (Fe3Al2(SiO4)3)

Pegmatite (Granitic)

Granitic Pegmatite

River Jasper (Chert/Chalcedony mix)

Silicon Dioxide (SiO2) with iron oxide and chlorite inclusions

Granite Pebbles

Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8), and Mica)

Quartz Geode

Silicon Dioxide (SiO2) in Geode formation

Tree Agate

Silicon Dioxide (SiO2) with Chlorite inclusions

Druzy Chalcedony/Quartz on Fluorite core

Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)

Dendritic Agate or Manganese Nodule in Chert/Limestone

Silicon Dioxide (SiO2) with Manganese Oxide (MnO2) inclusions

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)

Greenschist

Greenschist (chlorite schist)

Greenschist

Greenschist

Red Jasper (Beach Pebble)

SiO2 (Microcrystalline Quartz with Hematite inclusions)

Sandstone (Weathered Fragment)

Clastic Sedimentary Rock

Granitic Pegmatite

Pegmatitic Granite

Banded Gneiss

Gneiss (Metamorphic rock composed of feldspar, quartz, and mica)

Geode (Unopened)

Crystalline Quartz or Chalcedony filled Geode (SiO2)

Amygdaloidal Basalt

Amygdaloidal Basalt containing Zeolite and Calcite inclusions

Fossil / Permineralized Bone

Tyrannosaurus rex fossil (Hydroxylapatite replaced by various minerals)