Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Category
Browse metamorphic or sedimentary depending on local grade specimens identified by the Rock Identifier community.
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Lapis Lazuli
Lapis Lazuli (Complex rock consisting primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2)
Lapis Lazuli
Lazurite-rich metamorphic rock ((Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Charoite
Charoite (K(Ca,Na)2Si4O10(OH,F)·H2O)
Lapis Lazuli
Na8[Al6Si6O24]n(S,Cl,SO4,OH)2
Coal (likely Anthracite)
Anthracite coal
Calcite
Calcite (Calcium Carbonate, CaCO3)
Red Siltstone
Siltstone (primarily quartz and feldspar sized 0.0039 to 0.0625 mm)
Quartz (likely milky quartz or a stained variety)
Silicon Dioxide (SiO₂)
Green Calcite
Calcium Carbonate (CaCO3)
Sandstone (Ferruginous/Banded)
Clastic Terrigenous Sandstone (SiO2 with Fe2O3 cement)
Labradorite
Labradorite (Ca,Na)(Al,Si)4O8
Conglomerate
Conglomerate (clastic sedimentary rock)
Breccia
Breccia (Clastic Sedimentary Rock)
Magnetite / Ironstone
Magnetite (Fe3O4)
Emerald / Fluorite
Beryl (Be3Al2Si6O18) / Fluorite (CaF2)
Ruby (Corundum)
Al2O3 (Aluminium oxide with Chromium impurities)
Orthoclase (Potassium Feldspar)
KAlSi3O8 (Potassium Aluminum Silicate)
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Sapphire (Corundum)
Corundum (Al2O3)
Pyrite
Iron Disulfide (FeS2)
Galena
Lead(II) sulfide (PbS)
Leopard Skin Jasper
Rhyolite (Silicon Dioxide with impurities), SiO2
Limonite Sandstone
Ferruginous Sandstone (Hydrated Iron Oxide)
Travertine (Tufa)
Terrestrial Sedimentary Limestone (CaCO3)
Quartzite
Quartzite (primarily SiO2)
Ironstone Pebble
Ferruginous sedimentary rock (Fe2O3 / FeO(OH) mixed with SiO2)
Ironstone (likely siderite or goethite-rich siltstone)
Ferruginous Siltstone
Conglomerate
Clastic Sedimentary Rock (Conglomerate)
Emerald with Matrix (Emerald in Mica Schist)
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Ferruginous Sandstone Pebble
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH) staining)
Banded Iron Formation (BIF)
Banded Iron Formation (composed primarily of Hematite [Fe2O3], Magnetite [Fe3O4], and Chert [SiO2])
Ventifact
Eolian Ventifact (often composed of basalt, chert, or quartzite)
Sandstone (specifically Arkose or Quartz Arenite)
Arenite (primarily SiO2 with possible Feldspar)
Emerald (Tumbled Beryl)
Beryllium Aluminum Silicate (Be3Al2Si6O18) with Chromium/Vanadium impurities
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
Sapphire
Corundum (Al2O3)
Muscovite (Mica) in Quartz Matrix
Muscovite (KAl2(AlSi3O10)(OH)2) and Quartz (SiO2)
Blue Chalcedony
Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)