Biogenic Material

Tektite (likely indochinite)

Natural silica-rich impact glass; predominantly amorphous SiO₂ with aluminum, iron, magnesium, calcium, and sodium

Polished dark agate or jasper specimen

Cryptocrystalline quartz (chalcedony), SiO₂; exact identification is uncertain from the image

Dendritic jasper/chalcedony

Silica-rich microcrystalline quartz (SiO₂) with manganese-oxide dendrites

Black-and-white bicolored pebble

Likely basalt with a pale felsic or carbonate coating/inclusion; exact identification requires testing

Blue Sphalerite (likely dyed or treated Druzy Quartz/Agate)

Zinc Sulfide (ZnS) or Silicon Dioxide (SiO2) with trade-name enhancement

Turquoise ring (likely stabilized or imitation turquoise)

Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O; exact material is uncertain from the image

Coquina

Coquina (Bioclastic Limestone)

Quartz-bearing pegmatitic rock, likely granite/pegmatite

Feldspar–quartz pegmatite; chiefly K-feldspar, plagioclase, quartz, and possible mica

Tiger’s-eye bead bracelet

Chatoyant quartz, principally quartz (SiO₂) with pseudomorphic fibrous crocidolite/goethite inclusions

Vesicular volcanic rock (likely scoria)

Scoria, a vesicular basaltic to andesitic volcanic rock

Iron-rich lateritic soil / weathered ferruginous rock

Laterite, primarily hydrated iron oxides (goethite/limonite) with clay minerals and quartz

Polished banded stone, likely black marble or banded gneiss

Graphitic banded marble or quartz-feldspar biotite gneiss; exact identification requires testing

Crushed Stone / Gravel

Aggregate (mixed lithology)

White pebbles (rock material not identifiable from the image)

Undetermined; the smooth, pale pieces could be quartz, quartzite, or another light-colored rock

Petrified Wood

Silicified Wood (SiO2)

Fossilized coral with attached shell

Likely fossil coral (Scleractinia or Tabulata), with a bivalve or gastropod shell; exact identification requires microscopy

Sandstone

Arenite (SiO2 primarily)

Smoky quartz (likely)

Quartz, silicon dioxide (SiO₂), smoky variety

Polished tiger’s-eye

Quartz variety, SiO₂, with crocidolite-derived iron inclusions

Tumbled orange agate or carnelian

Microcrystalline quartz (chalcedony), SiO₂; orange coloration commonly from iron oxides

Asphalt Concrete

Bituminous Concrete / Asphaltic Composite

Beads (likely glass or man-made material)

N/A (artificial material)

Note on Image Identification: Textile

N/A (Anthropogenic material)

Likely weathered quartz-rich rock fragment

Uncertain; possibly quartz-bearing granitic or metamorphic material (SiO₂-dominant)

Tumbled hematite

Hematite (Fe₂O₃), commonly sold as “magnetic hematite” when synthetic or magnetized

Faceted Gemstone

Unknown transparent mineral, possibly Diamond (C), Cubic Zirconia (ZrO2), Quartz (SiO2), or Glass

Pink quartz (rose quartz), possibly quartz-rich rock

Quartz, silicon dioxide (SiO₂), commonly rose quartz

Asphalt Chunk

Asphalt concrete

Weathered quartz-rich rock, possibly granite or quartzite

Indeterminate; likely quartz–feldspar aggregate, potentially granitic or quartzitic material

Quartzite

Quartzite (SiO2-rich metamorphic rock)

Sandstone

Arenite (primary component SiO2)

Sandstone

Arenite (SiO2 based)

Engineer Quartz/Quartzite

SiO2 (Silicon Dioxide with binders)

Ferrochrome Slag

Calcium-Aluminium-Magnesium Silicate Slag

Tumbled pink quartz, likely dyed

Quartz (silicon dioxide, SiO₂), probably artificially colored chalcedony or milky quartz

Limestone

Calcium Carbonate (CaCO3)

Tumbled turquoise

Turquoise, hydrated copper aluminum phosphate — CuAl₆(PO₄)₄(OH)₈·4H₂O

Tektite (Indochinite)

Tektite (High-silica impact glass)

Chert Pebble

Microcrystalline silica (SiO2)

Tumbled quartz-rich stone, likely orange chalcedony or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite; orange coloration from iron oxides

Turquoise jewelry beads/earrings

Turquoise, hydrated copper–aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O; possibly reconstructed or imitation turquoise

Fossil bivalve shell

Ribbed pectinid or related bivalve; originally calcite/aragonite (CaCO₃), likely partially mineralized