Granite Pebble
Phaneritic intrusive igneous rock
igneous
Category
Mineral Precipitate (Anthropogenic Context)
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Learn about Mineral Precipitate (Anthropogenic Context) in the encyclopedia
View all →
Diamond in Kimberlite
Kimberlite Matrix with Carbon (Diamond)
igneous
Granite
Granite
Igneous
Granite
Granite
igneous
Granite
Granite
Igneous
Sandstone (likely Graywacke or Arkose)
Clastic Sedimentary Rock (primarily SiO2 with various lithic fragments)
sedimentary
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Mineral
Peridot (likely, based on color and appearance)
Olivine group mineral, specifically (Mg,Fe)2SiO4 (Forsterite-Fayalite solid solution series)
Mineral
Sandstone (Quartz Arenite)
Sandstone (SiO2 with possible mineral cements)
sedimentary
Garnetiferous Quartzite (Garnet Gneiss Pebble)
Garnet-bearing Quartzite or Quartz-Feldspar Gneiss
metamorphic
Jasper
Silicon dioxide (SiO2)
sedimentary
Jasper
Jasper (Cryptocrystalline Quartz, SiO2)
sedimentary
Unopened Geode
Geode (containing various mineralization like Quartz SiO2)
sedimentary
Rhodonite with Manganese Oxides
Rhodonite (Mn,Fe,Mg,Ca)SiO3
metamorphic
Granite
Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)
igneous
Galena
Lead(II) sulfide (PbS)
mineral
Copper Ore (likely Malachite or Chrysocolla staining)
Copper Secondary Mineral (e.g., Cu2CO3(OH)2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Peacock Ore (Bornite or Iridescent Chalcopyrite)
Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with oxidation
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Pyrite
Iron Disulfide (FeS2)
mineral
Geode (Unopened)
Silicon Dioxide (SiO2) in sedimentary host rock
sedimentary
Lapis Lazuli (Tumbled Stone)
Na6Ca2(Al6Si6O24)(SO4,S,Cl)2 (Lazulite-rich Metamorphic Rock)
metamorphic
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Blue Quartz with Graphite/Tourmaline Inclusions
Silicon Dioxide (SiO2) with Carbon (C) or Schorl elements
mineral
Quartz (Raw and Water-worn)
Silicon Dioxide (SiO2)
mineral
Rose Quartz
Silicon Dioxide (SiO2)
mineral
Sunstone
Oligoclase (Feldspar variety)
mineral
Amethyst
Silicon dioxide with iron impurities (SiO2 + Fe3+)
mineral
Orbicular Jasper (Ocean Jasper)
Silicon Dioxide (SiO2) with various inclusions
mineral
Amazonite
Microcline (variety Amazonite), K(AlSi3O8)
mineral
Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Alexandrite
Chrysoberyl (BeAl2O4 with Chromium impurities)
mineral
Limonite Pseudomorph after Pyrite
Limonite (Hydrous iron oxides e.g., FeO(OH)·nH2O) pseudomorphing Pyrite (FeS2)
mineral
Herkimer Diamond
Double-terminated Quartz (Silicon Dioxide, SiO2)
mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with trace Iron (Fe3+)
mineral
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Gold Nugget (Placer Gold)
Native Gold (Au)
mineral
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
mineral
Arfvedsonite with Garnet
Na3(Fe2+,Mg)4Fe3+Si8O22(OH)2
igneous