Gold
Native Gold (Au)
Category
Browse sedimentary (secondary classification for a weathered mineral specimen) specimens identified by the Rock Identifier community.
Gold
Native Gold (Au)
Blue Sapphire
Corundum (Al2O3 with trace Titanium and Iron)
Chert Pebble
Microcrystalline silica (SiO2)
Quartzite
Quartzite (primarily SiO2)
Granite
Granite (a plutonic igneous rock)
Granite
Phaneritic Plutonic Igneous Rock (Rich in SiO2)
Muscovite Schist with Quartz
Mica Schist (KAl2(AlSi3O10)(OH)2)
Quartzite
Quartzite (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Fossiliferous)
Silicon dioxide (SiO2)
Brown Agate
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (complex metamorphic silicate rock)
Gneiss
High-grade metamorphic rock (Gneiss)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert / Flint with Cortex
Silicon Dioxide (SiO2)
Jasper
Jasper (Cryptocrystalline variety of Quartz, SiO2)
Chert (Pink Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with impure Iron oxides
River Cobble (Basaltic/Andesitic)
Mafic Igneous Porphyritic Rock
N/A (Non-Geological Object)
Gold Nugget
Native Gold (Au)
Jasper Agate (Chalcedony)
Silicon Dioxide (SiO2)
Chert (Jasper/Limonitic Chert)
Microcrystalline Quartz (SiO2)
Amethyst (Tumbled/Weathered Quartz)
Amethyst (SiO2 with iron impurities)
Granite
Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)
Quartz Pebble
Silicon Dioxide (SiO2)
Jasper (Multi-colored) / Sea Glass Slag
Silicon Dioxide (SiO2) with impurities of Iron Oxide
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Quartzite and Chert
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)
Chrysoprase (Nickel-bearing Chalcedony)
Silicon Dioxide (SiO2) with traces of Hydrous Nickel Silicates
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Quartzite
Quartzite (Primary mineral: SiO2)
Fairburn Agate
Cryptocrystalline Quartz (SiO2)
Fossilized Shell in Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (specifically Flint or Jasper variant)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Granite
Granite (Phaneritic intrusion / SiO2 + KAlSi3O8 + NaAlSi3O8)
Quartzite Cobble
Metamorphosed Quartz Sandstone (primarily SiO2)
Sulfur on Aragonite
Sulfur (S) and Aragonite (CaCO3)
Chert (Pebble)
Chert (Microcrystalline Quartz, SiO2)