Man Made Material (Anthropogenic 'Mineraloid')

Chert (Flint/Chalcedony)

Silicon Dioxide (SiO2)

Chert Arrowhead

Chert (Cryptocrystalline variety of Quartz, SiO2)

Raw Diamond

Carbon (C)

Chert (Common Opal/Jasper variety)

Cryptocrystalline Quartz (SiO2)

Chert (and/or Flint)

Microcrystalline Quartz (SiO2)

Diamond (in jewelry setting)

Carbon (C)

Tumbled chalcedony or quartz pebble

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

Polished brecciated jasper pendant

Jasper, an opaque microcrystalline variety of chalcedony (mostly SiO₂), with iron-oxide staining and likely brecciation

Blue gemstone cross pendant

Likely faceted blue topaz (Al₂SiO₄(F,OH)₂); identification is uncertain from the image

Amber-bearing rough specimen

Fossilized plant resin (amber; organic mineraloid), commonly succinite

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint)

Chert (SiO2)

Chert (Green Chert or Jasper)

Microcrystalline Quartz (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (varietal Chalcedony or Flint)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Chert (Flint)

Microcrystalline Quartz (SiO2)

Coquina

Biogenic Limestone (Coquina)

Diamond

Native Carbon (C)

Red Sandstone

Arenite (Fe2O3 enriched)

Chert (Flint)

Silicon Dioxide (SiO2)

Goldstone

N/A (Synthetic Glass with Copper Inclusions)

Pale green aventurine (likely quartz) sphere

Quartz, SiO₂; possibly pale green aventurine, with color from inclusions or treatment

Green Quartzite

Metamorphic Quartzite (often colored by chromium-bearing minerals or fuchsite)

Sandstone

Arenite (composed primarily of SiO2)

Likely tumbled epidote-bearing rock or green jasper

Epidote-group silicate, possibly in a jasper or serpentinite matrix

Concrete or asphalt-like aggregate surface with a dark fragment

Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock

Beaded blue-and-green gemstone jewelry

Likely dyed or treated chalcedony/agate and green aventurine or glass-like stone; exact identification requires testing

Unknown dark mineral/rock fragment

Indeterminate; possibly a dark sulfide mineral or slag-like geological fragment

Sunstone (Aventurine Feldspar)

(Ca,Na)((Al,Si)2Si2O8) with inclusions of Cu or Fe2O3

Red Sandstone

Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)

Banded agate cabochon

Microcrystalline quartz (chalcedony), SiO₂

Turquoise cabochon ring

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

Polished greenstone pebble

Likely nephrite jade (tremolite–actinolite), though serpentine or greenstone is possible from appearance alone

Luminous Stone (Glow-in-the-dark Synthetic/Man-made Stone)

Strontium Aluminate tinted glass or resin (Crystalline silicate/oxide mix)

Polished hematite (specimen identification uncertain)

Hematite, α-Fe₂O₃

Conglomeratic concrete or asphalt aggregate surface with dark bituminous chunks

Polymictic gravel aggregate; dark pieces likely bitumen/asphalt, not a natural rock

Chert (with nodule)

Microcrystalline Quartz (SiO2)

Iron-stained quartz-rich rock, possibly jasper or chert

Microcrystalline quartz (SiO₂) with iron oxides/hydroxides

Aquamarine-like beryl pendant

Beryl, Be₃Al₂Si₆O₁₈; the beads may be dyed or treated chalcedony/amazonite, so image-only identification is uncertain

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Polished black stone pendant

Likely black obsidian or black tourmaline; exact identification is uncertain from the photograph