Anthropogenic Specimen (Man Made)

Chert (Common Opal/Jasper variety)

Microcrystalline Quartz (SiO2) with hydration

Rough Agate/Chert Nodules

Cryptocrystalline Quartz (SiO2)

Siltstone or Mudstone

Argillaceous sedimentary rock

Quartz with Iron Stains

Quartz (SiO2) with iron oxide/hydroxide staining

White Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Sandstone

Arenite (primarily SiO2)

River Cobble (likely Basalt or Metagraywacke)

Non-specific water-worn lithic fragment

Beach Pebble (likely Quartz or Chalcedony)

Silicon Dioxide (SiO2)

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Quartzite (Yellow/Iron-Stained)

Quartzite (SiO2 with Iron Oxide impurities)

Fossilized Sea Urchin (Echinoid)

Echinoidea (Fossil specimen, often replaced by Calcite or Silica)

Basalt (with possible quartz veinsing)

Basalt

Green Fluorite in Host Rock

Fluorite (Calcium Fluoride, CaF2)

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Blue Apatite

Fluorapatite / Chlorapatite [Ca5(PO4)3(F,Cl,OH)]

Sandstone (likely Arkose)

Arenite (composed mainly of SiO2 with Feldspar)

Green Calcite

Calcium Carbonate (CaCO3)

Dragon Vein Agate

Chalcedony (cryptocrystalline silica, SiO2) variety Agate

Quartzite with Iron Inclusions

Metamorphic Quartzite (SiO2 with Fe2O3 trace impurities)

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Beryl (var. Heliodor or Aquamarine)

Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)

Jasper Beach Pebble

Silicon Dioxide (SiO2) - Macro-crystalline Quartz

Quartz Pebble

Silicon Dioxide (SiO2)

Diorite (with Iron Staining)

Phaneritic Intermediate Igneous Rock

Basalt (Arrowhead form)

Extrusive mafic igneous rock

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Blue Chalcedony (Tumbled)

Silicon Dioxide (SiO2)

Picture Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Beryl (likely var. Aquamarine or Goshenite) in Matrix

Beryllium Aluminum Silicate (Be3Al2Si6O18)

White Quartz Pebble

Silicon Dioxide (SiO2)

Gastly (Trick or Trade Halloween Series)

Cellulose-carbonaceous composite (Lignocellulose laminated with pigmentary polymers)

Jasper with Quartz inclusions

Silicon Dioxide (SiO2) - Microcrystalline Chalcedony

Pink Quartzite

Quartzite (primarily SiO2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Ocean Jasper (Orbicular Jasper)

Silicon Dioxide (SiO2) with iron and magnesium inclusions

Labradorite (specifically Larvikite beads)

Plagioclase Feldspar (Na,Ca)(Si,Al)4O8

Red Moss Agate (Jasper)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Quartz

Quartz (Silicon Dioxide, SiO2)

Biotite Schist

Biotite-rich Schist (K(Mg,Fe)3AlSi3O10(F,OH)2)

Banded Agate (Carnelian type)

Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony

Amazonite

Potassium Feldspar (Microcline) - KAlSi3O8