Gold Nugget
Native Gold (Au)
Category
Browse anthropogenic (man made artifact) specimens identified by the Rock Identifier community.
Gold Nugget
Native Gold (Au)
Granite
Granite (Alkali feldspar, Plagioclase feldspar, and Quartz)
River Rock (Quartzite/Chert conglomerate)
Quartzite (SiO2)
Apache Tear (Obsidian)
Obsidian / Amorphous Volcanic Glass (primarily SiO2)
Quartz (Milky or White Quartz)
Silicon Dioxide (SiO2)
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Citrine
Silicon Dioxide (SiO2) with iron impurities
Banded Chert (Agate-like Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Quartz Pebble
Silicon Dioxide (SiO2)
Granodiorite
Granodiorite
Quartzite
Quartzite (mostly SiO2)
Hag Stone
Perforated Sedimentary Rock (typically Limestone or Sandstone)
Satin Spar (Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Clear Quartz
Silicon Dioxide (SiO2)
Quartz (likely macrocrystalline variety)
Quartz (SiO₂)
Chert (Limestone-based)
Silicon dioxide (SiO2)
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Milky Quartz Geode Fragment
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartz (Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Moqui Marble (Moqui Ball)
Ironstone Concretion (Goethite/Hematite cemented Sandstone)
Yellow Quartzite
Quartzite (SiO2)
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Granite
Granite (Mainly Quartz: SiO2, Feldspar: KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8, and Mica)
Gold Nugget
Native Gold (Au)
Hag Stone
Calcareous sedimentary rock (often Chert, Flint, or Limestone)
Chert (Nodule)
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed primarily of Quartz, SiO2)
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Limonite (with goethite)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
Orange Calcite
Calcite (CaCO3)
Smoky Quartz
Silicon Dioxide (SiO2)
Amethyst (Druze)
Silicon Dioxide (SiO2) with iron impurities
Granodiorite
Phaneritic intrusive igneous rock (Granodiorite)
Sandstone (Quartzite Pebble)
Arenite / Metamorphosed Sandstone (SiO2)
Chert (Chert Nodule)
Microcrystalline quartz (SiO2)
Granite
Granite (a common rock type, not a single mineral species)
Quartz
Quartz (SiO₂)
Red Jasper
Silicon dioxide (SiO2) with iron oxide impurities
Petrified Wood
Silicified Wood (primarily SiO2)