Black Diamond / Black Sapphire
Carbon (C) or Corundum (Al2O3)
Category
Browse marble specimens identified by the Rock Identifier community.
Black Diamond / Black Sapphire
Carbon (C) or Corundum (Al2O3)
Quartzite
Quartzite (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Green Quartzite
Metamorphic Quartz (SiO2) with Chromium-rich inclusions (Fuchsite)
Orange Calcite
Calcite (Calcium Carbonate - CaCO3)
Orange Calcite with Siderite/Iron Oxide Coating
Calcium Carbonate (CaCO3)
Banded Calcite (often sold as Onyx Marble)
Calcium Carbonate (CaCO3)
Orange Calcite (Cleavage Rhomb)
Calcite (Calcium Carbonate, CaCO3)
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)
Lapis Lazuli
Lazurite-rich metamorphic rock
Blue Calcite
Calcium Carbonate (CaCO3)
Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Blue Spinel on Marble with Phlogopite
MgAl2O4 (Spinel) in CaCO3 (Calcite/Marble) matrix
Quartzite
Quartzite (primarily SiO2)
Graphite
Graphite (Native Carbon, C)
Quartzite with Iron Inclusions
Quartzite (primarily SiO2)
Quartzite River Rock
Metamorphic Quartzite (primarily SiO2)
Quartzite
Quartzite (Mainly SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartzite
Quartzite (SiO2)
Quartzite with Feldspar
Quartzite (mainly SiO2) with inclusions of Potassium Feldspar (KAlSi3O8)
Quartzite pebble
Quartzite (SiO2)
Honey Calcite
Calcium Carbonate (CaCO3)
Banded Calcite (Mexican Onyx)
Calcium Carbonate (CaCO3)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, Mg3Si2O5(OH)4)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Ruby (Corundum)
Aluminum oxide (Al2O3) with Chromium traces
Ruby (in jewelry)
Corundum (Al2O3 with Chromium traces)
Blue Calcite
Calcium Carbonate (CaCO3)
Emerald with Matrix (Emerald in Mica Schist)
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Star Ruby
Corundum (Al2O3 with chromium and rutile inclusions)
Lapis Lazuli (Carved)
Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)
Ruby
Corundum (Al2O3 with Chromium traces)
Blue Sapphire (likely costume glass imitation)
Corundum (Al2O3) with iron/titanium impurities
Ruby in Matrix
Corundum (Al2O3)
Larimar
Pectolite (NaCa2Si3O[OH])