Yellow Quartz (Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Category
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Yellow Quartz (Citrine Quartz Pebble)
Silicon Dioxide (SiO2)
Amazonite
Amazonite (KAlSi3O8); a green variety of Microcline feldspar
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
Rough Citrine Quartz
Citrine (Silicon Dioxide, SiO2 with iron impurities)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
Blue Kyanite
Kyanite (Al2SiO5)
Basalt (with possible Olivine inclusions)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Quartz with Limonite Staining
Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)
Ferruginous Sandstone
Arenite with Iron-oxide cement (composed of Quartz and Limonite/Hematite)
Quartz Geode (Cracked)
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (predominantly Quartz with Hematite cementation)
Fossiliferous Limestone
Bioclastic Limestone (composition: CaCO3)
Wishing Stone (Gneiss or Basalt with Quartz Vein)
Gneiss or Metabasalt (with a Quartz or Calcite intrusion)
Garnet (likely Almandine)
Almandine Garnet, Fe3Al2(SiO4)3
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Malachite Coating on Host Rock
Malachite [Cu2CO3(OH)2]
Diorite (River Rock)
Intermediate plutonic igneous rock
Granite
Granite (Phaneritic Igneous Rock)
Gneiss
Gneiss
Sandstone
Arenite (SiO2 based with quartz grains)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
Sandstone (Micaceous Sandstone)
Arenite (SiO2 with KAl2(AlSi3O10)(OH)2 inclusions)
Pearl
Biogenic CaCO3 (Aragonite and Calcite)
Ironstone Concretion
Siderite or Ferruginous Concretion (FeCO3 or Iron Oxides)
Limestone with Bitumen/Chert
Calcite (CaCO3) containing organic hydrocarbons
Vesicular Basalt with Secondary Mineral Inclusions
Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Raw Corundum (Sapphire/Ruby variant)
Aluminum oxide (Al2O3)
Granodiorite Pebble
Granodiorite
Aquamarine (Pendant) and Jasper (Beads)
Beryllium aluminum silicate (Be3Al2Si6O18) with Chalcedony (SiO2)
Hypersthene
(Mg,Fe)SiO3 - Enstatite-Ferrosilite series
Moonstone
Orthoclase (Potassium aluminum silicate - KAlSi3O8)
Chalcedony on Matrix
Silicon Dioxide (SiO2)
Granite
Phaneritic Felsic Igneous Rock
Granite
Granite (Felsic Plutonic Rock)
Sandstone (Quartzose Sandstone)
Arenite
Fluorite (likely Fluorite on Quartz/Matrix)
Calcium Fluoride (CaF2)
Quartz / Common Opal Transition
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sulfide Ore (likely Galena and Sphalerite in Quartz)
Lead-Zinc Ore (PbS and ZnS)
Basalt with Quartz/Calcite Vein
Basalt (Mafic Volcanic Rock with secondary mineralization)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)