Marble

Lapis Lazuli (polished cabochon/sphere)

Na8[Al6Si6O24]Sn with accessory minerals (Pyrite, Calcite)

Likely calcite-rich limestone

Calcite (CaCO₃), probably micritic or fossiliferous limestone

Likely quartzite pebble

Quartzite, composed predominantly of quartz (SiO₂)

Polished green-and-white stone, possibly serpentine or jade

Tentatively serpentine (Mg₃Si₂O₅(OH)₄) or nephrite jade (interlocking amphibole fibers)

Orange Calcite

Calcium Carbonate (CaCO3)

White Calcite

Calcium Carbonate (CaCO3)

Banded Calcite (often sold as 'Mexican Onyx')

Calcium Carbonate (CaCO3)

Pink calcite marble (probable)

Calcite, CaCO₃; recrystallized limestone (marble)

Sandstone Concretion

Moqui Marble (Iron-oxide concretion)

Polished gray metamorphic pebble, likely marble or quartzite

Uncertain; possibly calcitic marble (CaCO₃) or quartzite (SiO₂) with dark mineral veining

Banded Calcite / Onyx Marble

Calcite (Travertine / Onyx Marble, CaCO3)

Yellowish calcite-rich rock, likely marble or limestone

Calcite (CaCO₃), possibly recrystallized as marble

Likely calcite fragment

Calcite (CaCO₃), possibly limestone or marble

Banded calcite (likely marble or calcite-rich limestone)

Calcite, CaCO₃; possibly calcitic marble

Tumbled zebra calcite (likely calcite marble)

Calcite, CaCO₃; commonly recrystallized limestone/marble with dark graphite- or carbon-rich bands

White calcite (likely tumbled calcite or marble fragment)

Calcite, calcium carbonate (CaCO₃); if the specimen is granular and rock-like, it may be marble, a calcite-rich metamorphic rock

Brecciated marble (decorative stone slab)

Calcite-rich marble breccia; chiefly calcite (CaCO₃), potentially with dolomite and minor iron oxides

Banded calcite (onyx marble)

Calcite, CaCO₃; commonly sold as “honey onyx” or “Mexican onyx”

White-veined gray limestone or marble

Calcite-rich carbonate rock; likely calcitic marble (CaCO₃)

Polished fossiliferous limestone, likely fossil shell fragment

Calcite-rich limestone (CaCO₃), possibly bioclastic/coquina limestone

Fossiliferous limestone, likely crinoidal limestone

Bioclastic limestone; predominantly calcite (CaCO₃), with possible dolomite and silicate impurities

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Blue Calcite

Calcium Carbonate (CaCO3)

Yellow Calcite

Calcium Carbonate (CaCO3)

Lapis Lazuli

Lapis Lazuli (Complex silicate rock containing Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Banded calcite (likely polished limestone/marble fragment)

Calcite, CaCO₃; probable banded calcitic marble

Serpentine

Serpentine Group (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3(Si, Al, Fe)2O5(OH)4

Honey calcite (likely calcite-rich marble or vein fragment)

Calcite, calcium carbonate (CaCO₃)

Sapphire (Blue/Violet Rough)

Corundum (Al2O3)

Ruby (Cabochon)

Corundum (Al2O3)

Sapphire

Corundum (Al2O3)

Rhodonite

Manganese Silicate (MnSiO₃)

Lapis Lazuli

Lazurite-dominant metamorphic rock, Na8[Al6Si6O24]n(S,Cl,SO4,OH)2

Ruby

Corundum (Al2O3 with chromium impurities)

Sapphire in a ring

Corundum (Al2O3)

Orange Calcite

Calcium Carbonate (CaCO3)

Milky Quartz

Silicon Dioxide (SiO2)

Quartzite

Metamorphosed Quartz Sandstone

Quartzite

Quartzite (primarily SiO2)

Red Quartzite / Ferruginous Quartz

Quartzite (primarily Silicon Dioxide, SiO2 with Iron Oxide impurities)