Man Made Material

Coquina

Biogenic Limestone (Calcite, CaCO3)

Tumbled amber-colored chalcedony or jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper

Tumbled purple quartz, likely amethyst or lavender quartz

Quartz (SiO₂), probably iron-colored amethyst; exact variety uncertain from the image

Sandstone

Sandstone (composed predominantly of Quartz, SiO2, with Feldspar and Clay minerals)

Quartzite

Metamorphic Quartzite (SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (SiO2 primarily)

Yellow chalcedony (likely lemon agate or yellow jasper)

Microcrystalline quartz, SiO₂; possibly iron-bearing jasper or chrysoprase-like chalcedony

Artificial Rock Face (Faux Rock)

Glass Fiber Reinforced Concrete (GFRC)

Heart-shaped faceted gemstone pendant

Likely yellow quartz (citrine) or synthetic yellow stone, set in metal with small clear accent stones

Unakite

Altered Granite (Epidotized Granite)

Tumbled orange chalcedony / jasper

Microcrystalline quartz, SiO₂, likely iron-stained chalcedony or quartz-rich jasper

Sandstone

Arenite

Chert (variations include Flint/Novaculite)

Chert (formula: SiO2)

Chert (often called Flint for darker varieties)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (and Jasper/Chalcedony mixture)

Microcrystalline Quartz (SiO2)

Sandstone

Clastic sedimentary rock (Quartz arenite/Arkose)

White Marble

Recrystallized Calcite (CaCO3)

Polished yellow-green serpentine pendant

Serpentine-group minerals, chiefly antigorite and/or lizardite; approximate formula Mg3Si2O5(OH)4

Blue Slag Glass

Amorphous Silica (Byproduct of smelting)

Cardstock (Paper)

Cellulose (C6H10O5)n

Synthetic Resin (Artificial Specimen)

Polyurethane or Polyester Resin

Slag Glass (Cullet)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Slag (Anthropogenic Glass/Iron byproduct)

Ferro-silicate Slag

Coal (Anthracite / Bituminous)

Organic Sedimentary Rock (Carbon-based)

Tree Agate

Chalcedony (SiO2)

Chert (Nodule)

Chert (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (and Flint)

Silicon Dioxide (SiO2)

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Diamond (in jewelry setting)

Adamantine Carbon (C)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Decorated turquoise-like bead or mineral pendant

Likely turquoise [CuAl₆(PO₄)₄(OH)₈·4H₂O], possibly dyed composite or blue-green jasper

Sandstone

Arenite

Yellow chalcedony (likely polished/tumbled pieces)

Microcrystalline quartz, SiO₂; commonly called yellow jasper or silicified limestone depending on exact texture

Rounded quartz pebble

Quartz (silicon dioxide, SiO₂)

Rounded pink granite cobble

Granite, chiefly quartz–alkali feldspar–plagioclase–biotite

Blue-green gemstone ring, likely treated turquoise or synthetic/treated beryl

Indeterminate from image; possibilities include turquoise (CuAl6(PO4)4(OH)8·4H2O), apatite, or treated beryl

Sea Glass

Amorphous Silicon Dioxide (SiO2)

Crackle Glass (Simulated Gemstone)

Amorphous Solid (SiO2)

Blue Goldstone

Aventurine glass (Synthetic borosilicate glass with cobalt and metallic inclusions)

Green Glass Slag

Amorphous Silicon Dioxide (SiO2) with metal oxide impurities