Sandstone
Clastic sedimentary rock (primarily SiO2)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Sandstone
Clastic sedimentary rock (primarily SiO2)
Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Sunstone
Oligoclase or Andesine (Plagioclase Feldspar) - (Ca, Na)((Al, Si)2Si2O8)
Smoky Quartz
Smoky Quartz (SiO2)
Fuchsite
Chromium-bearing Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2]
Industrial Diamond (Bort or Boart)
Diamond (pure Carbon, C)
Banded Agate (specifically Lake Superior Agate type)
Silicon Dioxide (SiO2) - Microcrystalline Chalcedony
Rhodonite
Rhodonite (Mn2+SiO3)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)
Amethyst
Quartz (SiO2) variety
Chert (Jasper/Opaline variety)
Silicon Dioxide (SiO2)
Rough Emerald Crystals
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Limonite with Trace Fossils
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
Sedimentary Breccia
Clastic Breccia (CaCO3/SiO2 matrix)
Orange Calcite
Calcium Carbonate (CaCO3)
Pyrite
Iron Sulfide (FeS2)
Moqui Marble (Concretion)
Iron Oxide Concretion (Hematite-cemented Sandstone)
Eclogite
Eclogite (Omphacite-Garnet Rock)
Rhodonite
Manganese Inosilicate (Mn,Fe,Mg,Ca)SiO3
Aquamarine
Beryl (Be3Al2Si6O18)
Smoky Quartz (with Iron Oxidation)
Silicon Dioxide (SiO2)
Black Obsidian
Volcanic Glass (SiO2 + impurities like Fe3O4)
Quartz (Common or Milky Quartz)
Silicon Dioxide (SiO2)
Eudialyte
Eudialyte (Na4(Ca,Ce)2(Fe2+,Mn,Y)ZrSi8O22(OH,Cl)2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Quartz (Milky/Clear Variety)
Silicon Dioxide (SiO2)
Obsidian
Amorphous Volcanic Glass (primarily SiO2)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Carnelian (Orange Agate/Chalcedony)
Silicon Dioxide (SiO2) - variety of Chalcedony
Milky Quartz Vein with Matrix
Silicon Dioxide (SiO2)
Prase or Green Quartz
Silicon Dioxide (SiO2 with actinolite or chlorite inclusions)
Amethyst (Quartz)
Silicon Dioxide (SiO2) with iron impurities
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Smoky Quartz
Smoky Quartz (SiO2)
Lapis Lazuli
Lapis lazuli (Mainly Lazurite: Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Red Quartz (Ferruginous Quartz)
Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)
Citrine
Silicon dioxide (SiO2)
Clear Quartz Crystal (Herkimer Diamond style)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
Amethyst (Geode)
Silicon Dioxide (SiO2) with iron impurities
Aquamarine
Beryl (Be3Al2Si6O18 with iron impurities)