Gold Nugget
Native Gold (Au)
Category
Browse sedimentary (if natural jasper) or artificial (if slag) specimens identified by the Rock Identifier community.
Gold Nugget
Native Gold (Au)
Agate Geode
Cryptocrystalline Quartz (SiO2)
Quartzite pebble
Metamorphic rock (mainly SiO2)
Greenstone
Greenschist / Greenstone (containing Chlorite, Epidote, Actinolite)
Basalt
Basalt (SiO2 percentage between 45% and 52%)
Milky Quartz
Silicon Dioxide (SiO2)
White Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Quartzite
Quartzite (SiO2)
Quartz Vein with Iron Staining
Silicon Dioxide (SiO2)
Pumice
Pumice (a highly vesicular volcanic glass)
Gold Ore in Matrix
Native Gold (Au) in Quartz/Limonite host rock
Basalt with Calcite Veins
Basalt (containing CaCO3 inclusions)
Basalt with Quartz/Calcite Veins
Basalt (Aphanitic Mafic Volcanic Rock) with Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) inclusions
Sapphire (Raw/Rough)
Corundum (Al2O3)
Greenstone / Quartzite Pebble
Metamorphosed Quartz-rich Rock
Garnet
Almandine (Fe3Al2(SiO4)3)
Diorite (River Cobble)
Phaneritic Intermediate Igneous Rock
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
Pumice
Pumice (Highly vesicular volcanic glass)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Basalt (Greenstone/Trap Rock)
Basalt (dominated by plagioclase feldspar and pyroxene)
Obsidian
Obsidian (volcanic glass), primarily SiO2 (silicon dioxide)
Pumice
Pumice (Amorphous volcanic glass)
Amber
Succinite (Approximate formula: C10H16O)
Yellow Quartzite Pebble
Quartzite (SiO2)
Quartz with Mica inclusion
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
Amber
Succinite (Approximate formula: C10H16O)
Slate
Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)
Amber
Succinite (specifically for Baltic amber); chemical formula approx. C10H16O
Quartz vein in Host Rock
Crystalline Silicon Dioxide (SiO2) in Lithic Matrix
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Quartzite (River Pebble)
Meta-quartzite (composed primarily of SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Conglomerate (Puddingstone)
Conglomerate (specifically, clastic sedimentary rock)
Ferruginous Quartz
Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3/FeO(OH))
Orthoclase (Potassium) Feldspar in Quartz
KAlSi3O8 (Potassium Aluminum Silicate)
Amethyst
Silicon dioxide (SiO2)
Rhodonite
Rhodonite (Mn,Fe,Mg,Ca)SiO3
Quartzite
Quartzite (primarily SiO2)
Agate Geode Node
Cryptocrystalline Quartz (SiO2)
Quartz Vein in Host Rock (Gabbro or Basalt)
Silicon Dioxide (SiO2) with Mafic Silicates
Pumice
Vesicular volcanic glass (primarily SiO2 with Al2O3)