Mineral Composite

Engineered Quartz Stone

Agglomerated Quartz (SiO2 + Polymer Resin)

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

Concrete aggregate surface

Human-made cementitious composite; primarily calcium-silicate-hydrate cement with mixed silicate aggregate

Banded Gneiss

Gneiss (pronounced 'nice')

Geode with Quartz and possibly Jasper/Hematite

Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides

White quartz in dark matrix (likely quartz-bearing breccia or polished composite specimen)

Quartz, SiO₂, in an unidentified dark silicate matrix

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

Polished gemstone tower assortment

Primarily quartz varieties and simulants; apparent amethyst (SiO₂), rose quartz (SiO₂), clear quartz (SiO₂), fluorite (CaF₂), sodalite, malachite, and possibly dyed or composite stones

Polymictic breccia, possibly volcanic breccia

Polymictic clastic breccia; likely a matrix-supported breccia containing lithic fragments, quartz, feldspar, and dark mafic minerals

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

Asphalt (Bituminous Concrete)

Bituminous mix / Anthropogenic conglomerate

Hand-Drawn Trading Card (Amateur Artwork)

Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)

Quartz (Engineered Stone Countertop)

Silicon Dioxide (SiO2) with polymer resins

Tumbled granite

Granite, a coarse-grained felsic intrusive igneous rock

Granite

Granite (Plutonic Igneous Rock)

Marble

Recrystallized Calcite (CaCO3)

Banded sandstone pebble

Quartz-rich lithic sandstone; exact provenance and composition require testing

Weathered granite

Granite, a quartz–feldspar–mica intrusive igneous rock

Banded Gneiss

Gneiss (Foliated Metamorphic Rock)

Dalmatian Stone

Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)

Rounded granitic pebble

Granite, a quartz–feldspar-rich plutonic rock

Gravel and Sediment Sample

Mixed clastic sediment

Tumbled granite pebble

Granite, a quartz–feldspar plutonic rock

Epidote

Ca2(Al,Fe)3(SiO4)3(OH)

Gneiss or Schist

Gneiss or Mica Schist with Garnet

Polished green tumbled stone, likely serpentine

Serpentinite (rock composed chiefly of serpentine-group minerals, approximately Mg₃Si₂O₅(OH)₄)

Limonite

FeO(OH)•nH2O

Limonite

FeO(OH)•nH2O

Serpentinite

Serpentinite, a rock composed mainly of serpentine-group minerals (approximately Mg₃Si₂O₅(OH)₄)

Limonite

FeO(OH)•nH2O

Tyrannosaurus Rex Fossil Skull

Tyrannosaurus rex

Granite

Felsic intrusive igneous rock

Limonite

FeO(OH)•nH2O

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Serpentinite (probable)

Serpentinite, a rock composed chiefly of serpentine-group minerals such as antigorite, lizardite, or chrysotile

Green serpentine-rich rock (possibly serpentinite)

Serpentinite, composed chiefly of serpentine-group minerals (e.g., lizardite, antigorite, or chrysotile)

Limonite

FeO(OH)•nH2O

Limonite

FeO(OH)•nH2O

Tumbled granite pebble

Granite, a coarse-grained felsic intrusive igneous rock

Fossil shark tooth

Shark tooth; species cannot be determined from the image

Gravel and Pebbles

Unconsolidated rock fragments / detrital sediment

Rough Diamond (Bort)

Diamond (C)