Marble

Red Quartzite / Ferruginous Quartz

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

Quartzite River Stone

Metamorphic Quartzite (primarily SiO2)

Polished green calcite (often marketed as “onyx marble” or “Pakistan onyx”)

Calcite, CaCO₃

Limestone

Micritic limestone, chiefly calcite (CaCO₃)

Fossilized oyster shell / oyster reef limestone

Predominantly calcite (CaCO₃), commonly fossil bivalve shells such as Ostrea or Crassostrea; matrix is bioclastic limestone

Yellow Quartzite

Quartzite (SiO2)

Banded Calcite (Honey Calcite)

Calcium Carbonate (CaCO3)

Honey Calcite

Calcium Carbonate (CaCO3)

Quartz-rich metamorphic rock, likely quartzite

Quartzite (mostly crystalline SiO₂), possibly quartz-rich schist or vein quartz

Yellow Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Fuchsite Gneiss (Green Quartzite)

Chromium-rich Muscovite (KAl2(AlSi3O10)(OH)2 with Cr replacements)

Calcite

Calcium Carbonate (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Likely limestone or marble fragment

Calcite-rich carbonate rock; possibly marble (CaCO₃)

Calcite

Calcite (Calcium Carbonate, CaCO3)

Likely weathered limestone or marble fragment

Calcite-rich carbonate rock; likely calcitic marble (CaCO₃), though limestone is also possible

Moqui Marble (Iron Concretion)

Hematite-Goethite Concretion

Orange Calcite

Calcium Carbonate (CaCO3)

Blue Calcite

Calcium Carbonate (CaCO3)

Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

White Marble (often sold as Caribbean Calcite or Pistachio Calcite in this form)

Recrystallized Calcite (CaCO3)

Polished banded calcite (onyx marble)

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

Likely weathered marble or calcite-rich metamorphic rock

Calcite (CaCO₃), probably marble; exact identification requires testing

Calcite

Calcium Carbonate (CaCO3)

Likely calcite fragment

Calcite (calcium carbonate, CaCO₃)

Quartzite

Quartzite (SiO2)

Quartzite with Hematite staining

Metamorphosed Sandstone (SiO2 with Fe2O3 inclusions)

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Quartzite

Quartzite (chiefly SiO2)

Quartzite

Quartzite (SiO2)

Quartzite (Stacked Stone Veneer)

Quartzite

Quartzite pebble

Quartzite (SiO2)

Quartzite

Quartzite (SiO2)

Larimar

NaCa2Si3O8(OH)

Tumbled white stone, possibly quartz or marble

Uncertain; likely quartz (SiO₂) or calcite-rich marble (CaCO₃)

Larimar

Blue Pectolite (NaCa2Si3O8(OH))

Larimar

Pectolite (NaCa2Si3O8(OH))

Optical Calcite

Calcium Carbonate (CaCO3)

Ruby

Corundum (Aluminum Oxide, Al2O3)

Blue Calcite

Calcium Carbonate (CaCO3)