Man Made Composite

Quartzite

Metamorphic Quartzite (SiO2)

Graphite

Graphite (elemental carbon, C)

Red Sandstone

Arenite (Ferruginous Sandstone)

Quartzite

Metamorphic Quartzite (SiO2)

Sandstone (Pebble)

Sandstone (arenite, arkose, wacke depending on composition)

Jasper

Silicon dioxide (SiO2) with impurities

Turquoise-colored beads, likely imitation turquoise

Turquoise is hydrated copper–aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O; these beads may be dyed or composite material

Quartzite

Metamorphic Rock (Mainly SiO2)

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

Obsidian (Black)

Obsidian (High-silica volcanic glass)

Diabase (Greenstone)

Diabase (Dolerite)

Fossil crinoid columnal in limestone

Crinoidea indet.; calcitic ossicle (CaCO₃)

Likely flint pebble (possibly a worked flint fragment)

Microcrystalline quartz (chalcedony), SiO₂; commonly called flint

Engineered Quartz

Silicon dioxide composite

Sandstone

Arenite

Likely polished leopard-skin jasper or brecciated jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image alone

Engineered Quartz

Engineered Stone (primarily SiO2)

Jade bangle

Likely nephrite jade (actinolite–tremolite amphibole); possibly jadeite

Sandstone (specifically Arkose or Quartz Arenite)

Arenite (primarily SiO2 with possible Feldspar)

Oak-grain Laminate (Industrial/Decorative Furniture Finish)

Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)

Red Sandstone

Arenite (with Iron Oxide / Hematite staining)

Limestone

Calcareous sedimentary rock (CaCO3)

Fossilized sea urchin

Echinoid test, likely a regular sea urchin; calcite (CaCO₃)

Ferruginous Sandstone (Ironstone)

Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)

Digital Multimeter (Synthetic Object)

Digital Multimeter (DMM)

Fossilized echinoid (sea urchin), likely a sand dollar fragment or small regular urchin

Echinodermata; commonly Clypeasteroida or Echinoida, preserved mainly as calcite (CaCO₃)

Weathered iron-rich rock, possibly jasper or ironstone

Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests

Conglomeratic concrete or asphalt aggregate surface with dark bituminous chunks

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

Dyed Blue Agate Slice

Silicon Dioxide (SiO2)

Small tumbled blue-green stone, possibly chrysocolla or turquoise

Indeterminate copper-bearing mineral; possible chrysocolla (Cu₂H₂Si₂O₅(OH)₄·nH₂O) or turquoise (CuAl₆(PO₄)₄(OH)₈·4H₂O)

Quartzite Pebble

Quartzite (SiO2)

Banded Calcite or Travertine

Calcium Carbonate (CaCO3)

Wood Paneling

Engineered Wood / Plywood Paneling

Pearl (likely Freshwater or Akoya Cultured)

Aragonite / Conchiolin composite (CaCO3)

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Black Pearl (Tahitian Type)

Aragonite / Conchiolin composite (CaCO3)

Opal ring (likely precious opal)

Hydrated amorphous silica, SiO₂·nH₂O; the pictured stone may be natural opal or a lab-created/imitation opal

Granite

Granite (felsic intrusive igneous rock)

Carved turquoise arrowhead/pendant

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

Possible ironstone concretion or weathered mineral nodule

Iron-oxide-rich concretion, likely goethite/limonite; identification uncertain from the photo

Small polished jasper or agate pebble

Likely microcrystalline quartz (SiO₂); exact variety cannot be determined from the photo

Polished tiger iron

Tiger iron; interlayered hematite, jasper, and crocidolite-quartz (often riebeckite)