Gold Nugget
Native Gold (Au)
Category
Browse mineral specimen specimens identified by the Rock Identifier community.
Gold Nugget
Native Gold (Au)
Metal Alloy (Likely Pewter or Sterling Silver)
Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).
Yellow Banded Agate
Silicon Dioxide (SiO₂)
Gold Ore / Native Gold
Native Gold (Au)
Gold
Native Gold (Au)
Petrified Wood
Silicified Wood (SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Granite Cobble
Granite (Phaneritic Quartz-Feldspar specimen)
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Banded Iron Formation (BIF) with Quartz
Banded Iron Formation, often composed of alternating layers of hematite (Fe2O3) or magnetite (Fe3O4) and chert (microcrystalline quartz, SiO2)
Granite Cobble/Pebble
Granite
Granite
Granite
Oolitic Limestone
Oolite (Sedimentary rock composed of CaCO3)
Granitic Pegmatite
Granite Pegmatite (typically containing Quartz SiO2, Feldspar KAlSi3O8, and Muscovite)
Chert (specifically Jasper/Carnelian Agate)
Microcrystalline Quartz (SiO2)
Optical Calcite (Iceland Spar)
Calcite (CaCO3)
Pyrite
Iron Sulfide (FeS2)
Yellow Quartzite (River Pebble)
Quartzite (SiO2)
Celestine (or Celestite)
Celestine (Strontium Sulfate, SrSO4)
Quartz (in matrix)
Quartz (SiO₂)
Quartz
Silicon Dioxide (SiO2)
Aragonite (variety 'Flos Ferri')
Aragonite (CaCO3)
Kyanite
Kyanite (Al2SiO5)
Opal
Hydrous silicon dioxide (SiO2·nH2O)
Jasper and Quartz River Cobble
Silicon Dioxide (SiO2) with Hematite inclusions
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Aquamarine on Feldspar Matrix
Beryl (Be3Al2Si6O18) with Potassium Feldspar (KAlSi3O8)
Calamites Fossil (Horsetail Stem)
Calamites (Genus), part of the class Equisetopsida
Red Jasper (River Polished)
Jasper (Silicon Dioxide, SiO2)
Halite (Rock Salt)
Halite; NaCl (Sodium Chloride)
Gold Nugget
Native Gold (Au)
Gold Nugget
Native Gold (Au)
Amazonite (Tumbled Chips)
Potassium Feldspar (KAlSi3O8)
Gold Nugget
Native Gold (Au)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
Ruby in Fuchsite (often confused with Ruby in Zoisite)
Corundum (Al2O3) in Chromium-rich Muscovite (KAl2(AlSi3O10)(OH)2)
Ferruginous Quartz
Quartz (Silicon Dioxide) with Iron Inclusion (SiO2 + Fe2O3)
Banded Gneiss (River Cobble)
Gneiss (a high-grade metamorphic rock)
Clear Quartz
Silicon Dioxide (SiO2)
Fish Fossil in Limestone
Lycoptera (likely) in Micritic Limestone
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)