Man Made Material (Simulated Mineral)

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Quartz-bearing Pegmatite with Metallic Sulfides

Pegmatite / Quartz-Feldspar Matrix with Pyrite and Mica

Botryoidal Chalcedony / Quartz

Silicon Dioxide (SiO2)

Quartz (Milky Quartz / Quartz Crystal)

Silicon Dioxide (SiO2)

Fire Opal (in matrix)

Hydrated Silica (SiO2·nH2O)

Chert

Chert (microcrystalline quartz)

Limonite (Iron Ore)

FeO(OH)·nH2O

Fossilized Tooth

Vertebrate Fossilized Tooth (Mineralized Biogenic Material)

Vuggy Quartz on Matrix

Silicon Dioxide (SiO2)

Quartz geode

Microcrystalline and crystalline quartz (SiO₂), likely chalcedony-lined geode

Jade (likely Nephrite Jade based on appearance)

Nephrite (a variety of actinolite, Ca2(Mg,Fe)5Si8O22(OH)2)

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrous ferric oxide)

Septarian Pebble

Septarian nodule / Concretion

Obsidian

Obsidian (volcanic glass, amorphous silica rich rock)

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Petrified Wood

Silicified Wood

Limonite (Ironstone)

Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))

Pyrite (Fool's Gold) Cube

Iron Sulfide (FeS2)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Shark Tooth Fossil

Carcharocles megalodon or similar extinct shark tooth

Iron-Stained Quartz

Silicon Dioxide (SiO2) with Iron Oxide/Limonite coating

Quartz Pebble with Epidote / Chlorite Inclusions

Silicon Dioxide (SiO2) with Epidote/Chlorite inclusions

Arfvedsonite with Garnet

Na3(Fe2+,Mg)4Fe3+Si8O22(OH)2

Likely basalt pebble

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine

Sandstone (Ferruginous)

Arenite (with Iron Oxide)

Fossilized Shark Tooth

Chondrichthyes (Class)

Sandstone

Arenite (primarily SiO2 with Fe2O3)

Polished Picasso jasper

Silicified carbonate rock, commonly marketed as Picasso jasper; composition varies and is not a single mineral species

Rough amethyst-bearing quartz specimens

Quartz, SiO₂; purple coloration from trace iron and irradiation

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Likely basalt with a pale mineral-filled vesicle

Vesicular basalt, probably containing calcite or zeolite (uncertain from image)

Banded malachite cabochon

Malachite, Cu₂CO₃(OH)₂; the dark bands may be manganese-oxide or other sulfide-rich matrix, and could also indicate a composite or treated specimen

Limestone or Sandstone Cobble

Sedimentary rock (Calcium carbonate or Quartz based)

Fluorite

Calcium Fluoride (CaF2)

Milky Quartz with Hematite/Limonite staining

Silicon Dioxide (SiO2)

Obsidian

Obsidian (volcanic glass)

Green Banded Chert (Agate/Jasper)

Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite

Fossil Shark Tooth

Carcharocles or Lamniformes (order)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Fossil Snail

Gastropoda (fossilized)

Tumbled green aventurine

Quartzite dominated by quartz (SiO₂), with green mica/fuchsite inclusions